Clinical Parasitology

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Clinical Parasitology

  1. 1. Parasitic Infections: Clinical Manifestations, Diagnosis and Treatment www.freelivedoctor.com
  2. 2. The Reality <ul><li>1.3 billion persons infected with Ascaris (1: 4 persons on earth) </li></ul><ul><li>300 million with schistosomiasis </li></ul><ul><li>100 million new malaria cases/yr </li></ul><ul><li>At UCLA, 38% of pediatric and dental clinic children harbored intestinal parasites </li></ul>www.freelivedoctor.com
  3. 3. Case1 <ul><li>42-yr-old previously healthy, UF professor </li></ul><ul><li>6-week history of intermittent diarrhea, flatus and abdominal cramps </li></ul><ul><li>Diarrhea: x8/day; pale; no blood or mucus </li></ul><ul><li>No tenesmus </li></ul><ul><li>Illness began slowly during camping trip to Colorado with loose stools </li></ul><ul><li>Spontaneously remission for 5-6 days at a time, then recur </li></ul>www.freelivedoctor.com
  4. 4. Case 1 <ul><li>His 8-yr-old son had had a mild course of watery diarrhea—ascribed to viral gastroenteritis by general practitioner </li></ul><ul><li>Stool smear—no pus cells </li></ul><ul><li>However, wet preps showed… </li></ul>www.freelivedoctor.com
  5. 5. www.freelivedoctor.com
  6. 6. www.freelivedoctor.com
  7. 7. Diagnosis? www.freelivedoctor.com
  8. 8. Giardiasis ( G. lamblia ) <ul><li>Should be suspected in prolonged diarrhea </li></ul><ul><li>Contaminated water often implicated—outbreaks </li></ul><ul><li>Campers who fail to sterilize mountain stream water </li></ul><ul><li>Person-person in day care centers </li></ul><ul><li>MSM </li></ul><ul><li>Symptoms usually resolve spontaneously in 4-6 weeks </li></ul>www.freelivedoctor.com
  9. 9. Giardiasis Tests of choice <ul><li>Examination of concentrated stools for cysts (90% yield after 3 samples) </li></ul><ul><ul><li>Usually no PMNs </li></ul></ul><ul><li>Stool ELISA, IF Antigen (up to 98% sensitive/90-100% specific) </li></ul><ul><li>Consider aspiration of duodenal contents--trophozoites </li></ul><ul><li>Treatment: Metronidazole for 5-7 days </li></ul>www.freelivedoctor.com
  10. 10. Case 2 <ul><li>40 y/o male vicar returned from 2 years of missionary work in South Africa </li></ul><ul><li>Excellent health throughout stay there </li></ul><ul><li>3 months after returning to U.S. </li></ul><ul><ul><li>Suddenly ill with abdominal distension </li></ul></ul><ul><ul><li>Fever </li></ul></ul><ul><ul><li>Periumbilical pain </li></ul></ul><ul><ul><li>Vomiting </li></ul></ul><ul><ul><li>Blood-tinged diarrheal stools </li></ul></ul><ul><li>Denied arthritis /known exposure to parasites </li></ul><ul><li>Family history of “inflammatory bowel disease” </li></ul>www.freelivedoctor.com
  11. 11. Case 2 <ul><li>Physical examination: </li></ul><ul><ul><li>Acutely ill </li></ul></ul><ul><ul><li>Distended abdomen </li></ul></ul><ul><ul><li>No hepatomegaly or splenomegaly </li></ul></ul><ul><ul><li>Decreased bowel sounds </li></ul></ul><ul><ul><li>Stool exam </li></ul></ul><ul><ul><ul><li>Gross blood present </li></ul></ul></ul><ul><ul><ul><li>No pus cells </li></ul></ul></ul><ul><ul><ul><li>Negative for O&P, one negative C&S </li></ul></ul></ul>www.freelivedoctor.com
  12. 12. Sigmoidoscopy revealed… <ul><li>Multiple punctate bleeding sites at 7 to 15 cm with normal appearing mucosa between sites </li></ul><ul><li>This mucosa easily denuded when pressure applied to it, leaving large areas of bleeding submucosa </li></ul>www.freelivedoctor.com
  13. 13. Case 2 <ul><li>Diagnosed with ulcerative colitis </li></ul><ul><li>Started on corticosteroids </li></ul><ul><li>Temperature rose to 40 °C </li></ul><ul><li>Abdomen distension increased and worsening of symptoms </li></ul><ul><li>Emergency laparotomy for toxic megacolon </li></ul>www.freelivedoctor.com
  14. 14. www.freelivedoctor.com
  15. 15. www.freelivedoctor.com
  16. 16. Diagnosis? www.freelivedoctor.com
  17. 17. Entamoeba histolytica <ul><li>One of 7 amoebae commonly found in humans </li></ul><ul><li>Only one that causes significant disease </li></ul><ul><li>Causes intestinal (diarrhea and dysentery) and extraintestinal (liver primarily) disease </li></ul><ul><li>In US </li></ul><ul><ul><li>Institutionalized patients </li></ul></ul><ul><ul><li>MSM </li></ul></ul><ul><ul><li>Tourists returning from developing countries </li></ul></ul><ul><ul><li>Patients with depressed cell mediated immunity </li></ul></ul>www.freelivedoctor.com
  18. 18. Trophozoites with ingested RBC www.freelivedoctor.com
  19. 19. Trophozoites in colon tissue (H & E stain) www.freelivedoctor.com
  20. 20. Cyst (wet mount) www.freelivedoctor.com
  21. 21. Amoebiasis: Clinical Manifestations <ul><li>Symptoms depend on degree of bowel invasion </li></ul><ul><ul><li>Superficial: watery diarrhea and nonspecific GI complaints </li></ul></ul><ul><ul><li>Invasive: gradual onset (1-3 weeks) of abdominal pain, bloody diarrhea, tenesmus </li></ul></ul><ul><li>Fever is seen in minority of patients </li></ul>www.freelivedoctor.com
  22. 22. Amoebiasis: Clinical Manifestations <ul><li>Can be mistaken for ulcerative colitis </li></ul><ul><li>Steroids can dramatically worsen and precipitate toxic megacolon </li></ul><ul><li>Amebic liver abscesses </li></ul><ul><ul><li>RUQ pain, pain referred to right shoulder </li></ul></ul><ul><ul><li>High fever </li></ul></ul><ul><ul><li>Hepatomegaly (50%) </li></ul></ul>www.freelivedoctor.com
  23. 23. Amoebic abscess—remember… <ul><li>Can occur in lung, brain, spleen </li></ul>www.freelivedoctor.com
  24. 24. Amoebic Abscess <ul><li>Liquefaction of liver cells </li></ul><ul><li>Do not contain pus </li></ul><ul><li>Anchovy paste sauce </li></ul><ul><li>Culture of contents usually sterile </li></ul><ul><li>Liver affected: </li></ul><ul><ul><li>53%-right lobe </li></ul></ul><ul><ul><li>8%-left lobe </li></ul></ul>www.freelivedoctor.com
  25. 25. www.freelivedoctor.com
  26. 26. www.freelivedoctor.com
  27. 27. Remember… <ul><li>That stool is merely a convenient vehicle passing by </li></ul><ul><li>Amoebae live the bowel wall </li></ul><ul><li>Direct observation preferable to mere examination of stool </li></ul><ul><li>Trophozoites best seen in direct scrapings of ulcers </li></ul>www.freelivedoctor.com
  28. 28. Amoebiasis Treatment <ul><li>Most respond to metronidazole </li></ul><ul><li>Open surgical drainage should be avoided, if at all possible </li></ul>www.freelivedoctor.com
  29. 29. Case 3 <ul><li>Previously healthy 3-year-old girl </li></ul><ul><li>Attends day-care center </li></ul><ul><li>7 day history of watery diarrhea </li></ul><ul><li>Nausea </li></ul><ul><li>Vomiting </li></ul><ul><li>Abdominal cramps </li></ul><ul><li>Low-grade fever </li></ul>www.freelivedoctor.com
  30. 30. www.freelivedoctor.com
  31. 31. Case 4 <ul><li>34 year-old AIDS patient </li></ul><ul><li>Debilitating, cholera-like diarrhea </li></ul><ul><li>Severe abdominal cramps </li></ul><ul><li>Malaise </li></ul><ul><li>Low-grade fever </li></ul><ul><li>Weight loss </li></ul><ul><li>Anorexia </li></ul>www.freelivedoctor.com
  32. 32. www.freelivedoctor.com
  33. 33. Diagnosis? Case 3 & 4 www.freelivedoctor.com
  34. 34. Three cysts stained pale red are seen in the center with this acid fast stain www.freelivedoctor.com
  35. 35. Modified acid-fast stain of stool showing red oocysts of Cryptosporidium parvum against the blue background of coliforms and debris www.freelivedoctor.com
  36. 36. Cryptosporidium parvum <ul><li>Causes secretory diarrhea: 10 liter/day </li></ul><ul><li>Significant cause of death in HIV/AIDS </li></ul><ul><li>Animal reservoirs </li></ul><ul><li>Incubation period: 5-10 days </li></ul>www.freelivedoctor.com
  37. 37. Cryptosporidium parvum <ul><li>Infants & young children in day-care </li></ul><ul><li>Unfiltered or untreated drinking water </li></ul><ul><li>Farming practices: lambing, calving, and muck-spreading </li></ul><ul><li>Sexual practices: oral contact with stool of an infected individual </li></ul><ul><li>Nosocomial setting with other infected patients or health-care employees </li></ul><ul><li>Veterinarians: contact with farm animals </li></ul><ul><li>Travelers to areas with untreated water </li></ul><ul><li>Living in densely populated urban areas </li></ul><ul><li>Owners of infected household pets (rare) </li></ul>www.freelivedoctor.com
  38. 38. Diagnosis and Treatment <ul><li>Best diagnosed by stool exam </li></ul><ul><li>No known effective treatment </li></ul><ul><li>Nitazoxamide shortens duration of diarrhea </li></ul>www.freelivedoctor.com
  39. 39. Case 5 <ul><li>Mr. & Mrs. R. were sailing with their 3 children in Jamaica </li></ul><ul><li>Living primarily on the boat with several day trips to a small coastal island </li></ul><ul><li>On island, ate several types of tropical fruit </li></ul><ul><li>Both became suddenly ill with fevers, chills, muscle aches, and loss of appetite. </li></ul><ul><li>Sought treatment locally, and were diagnosed with hepatitis, likely due to ingestion of toxic fruit </li></ul>www.freelivedoctor.com
  40. 40. Case 5 <ul><li>Two days later, Mr. R. became jaundiced and passed dark urine </li></ul><ul><li>He progressively worsened, became comatose and died </li></ul><ul><li>In the meantime, Mrs. R. was transferred to SUF for liver transplant </li></ul>www.freelivedoctor.com
  41. 41. Case 5 <ul><li>None of the children were sick despite having eaten the same fruits and other foods. </li></ul><ul><li>The family had taken chloroquine prophylaxis against malaria, but the parents stopped the medicine 2 weeks prior to becoming ill because of side effects. </li></ul>www.freelivedoctor.com
  42. 42. www.freelivedoctor.com
  43. 43. www.freelivedoctor.com
  44. 44. Falciparum vs. Vivax <ul><li>Location: Falciparum confined to tropics and subtropics; vivax more temperate </li></ul><ul><li>Falciparum infects RBC of any age; others like reticulocytes </li></ul><ul><li>Falciparum-infected RBCs stick to vascular endothelium causing capillary blockage </li></ul>www.freelivedoctor.com
  45. 45. www.freelivedoctor.com
  46. 46. www.freelivedoctor.com
  47. 47. Malaria: Genetic susceptibility <ul><li>Two genetic traits associated with decreased susceptibility to malaria </li></ul><ul><li>Absence of Duffy blood group antigen blocks invasion of Plasmodium vivax </li></ul><ul><ul><li>Significant number of Africans </li></ul></ul><ul><li>Persons with sickle cell hemoglobin are resistant to P. falciparum </li></ul><ul><li>Sickle cell disease and trait </li></ul>www.freelivedoctor.com
  48. 48. Malaria: Clinical manifestations <ul><li>Non-specific, flu-like illness </li></ul><ul><li>Incubation </li></ul><ul><ul><li>P. falciparum : 9-40 days </li></ul></ul><ul><ul><li>Non-P. falciparum : may be prolonged </li></ul></ul><ul><ul><ul><li>P. vivax : 6-12 months </li></ul></ul></ul><ul><ul><ul><li>P. malariae and ovale : years </li></ul></ul></ul><ul><li>Fever is the hallmark of malaria </li></ul><ul><ul><li>Classically, 2-3 day intervals in P. vivax and malariae </li></ul></ul><ul><ul><li>More irregular pattern in P. falciparum </li></ul></ul><ul><li>Fever occurs after the lysis of RBCs and release of merozoites </li></ul>www.freelivedoctor.com
  49. 49. Malaria: Clinical manifestations <ul><li>Febrile paroxysms have 3 classic stages </li></ul><ul><ul><li>Cold stage </li></ul></ul><ul><ul><ul><li>Pt feels cold and has shaking chills </li></ul></ul></ul><ul><ul><ul><li>15-60 mins. prior to fever </li></ul></ul></ul><ul><ul><li>Hot stage </li></ul></ul><ul><ul><ul><li>39-41 °C </li></ul></ul></ul><ul><ul><ul><li>Lassitude, loss of appetite, bone and joint aches </li></ul></ul></ul><ul><ul><ul><li>Tachycardia, hypotension, cough, HA, back pain, N/V, diarrhea, abdo pain, altered consciousness </li></ul></ul></ul><ul><ul><li>Sweating stage </li></ul></ul><ul><ul><ul><li>Marked diaphoresis followed by resolution of fever, profound fatigue, and sleepiness </li></ul></ul></ul><ul><ul><ul><li>2-6 hours after onset of hot stage </li></ul></ul></ul>www.freelivedoctor.com
  50. 50. Malaria: Clinical manifestations <ul><li>Other symptoms depend on malaria strain </li></ul><ul><li>P. vivax, ovale and malariae : few other sxs </li></ul><ul><li>P. falciparum : </li></ul><ul><ul><li>Dependent upon host immune status </li></ul></ul><ul><ul><li>No prior immunity/splenectomy  high levels of parasitemia  profound hemolysis </li></ul></ul><ul><ul><li>Vascular obstruction and hypoxia </li></ul></ul><ul><ul><ul><li>Kidneys: renal failure </li></ul></ul></ul><ul><ul><ul><li>Brain: (CNS) ― hypoxia, coma, seizures </li></ul></ul></ul><ul><ul><ul><li>Lungs: pulmonary edema </li></ul></ul></ul><ul><ul><li>Jaundice & hemoglobinuria (blackwater fever) </li></ul></ul>www.freelivedoctor.com
  51. 51. Malaria: Clinical manifestations <ul><li>Always suspect malaria in travelers from developing countries who present with: </li></ul><ul><ul><li>Influenza-like illness </li></ul></ul><ul><ul><li>Jaundice </li></ul></ul><ul><ul><li>Confusion or obtundation </li></ul></ul>www.freelivedoctor.com
  52. 52. Diagnosis <ul><li>Giemsa-stained blood smear </li></ul><ul><ul><li>Thick and thin smears </li></ul></ul><ul><li>P. falciparum: </li></ul><ul><ul><li>Best just after fever peak </li></ul></ul><ul><li>Others: </li></ul><ul><ul><li>Smears can be performed at any time </li></ul></ul><ul><li>Examine blood on 3-4 successive days </li></ul>www.freelivedoctor.com
  53. 53. Differences in strains <ul><li>P. falciparum </li></ul><ul><ul><li>No dormant phase in liver </li></ul></ul><ul><ul><li>Multiple signet ring trophs per cell </li></ul></ul><ul><ul><li>High percentage (>5%) parasitized RBCs considered severe </li></ul></ul>www.freelivedoctor.com
  54. 54. Differences in strains <ul><li>P. vivax and ovale </li></ul><ul><ul><li>Dormant liver phase </li></ul></ul><ul><ul><li>Single signet ring trophs per cell </li></ul></ul><ul><ul><li>Schuffner’s dots in cytoplasm </li></ul></ul><ul><ul><li>Low percent (< 5%) of parasitized RBCs </li></ul></ul>www.freelivedoctor.com
  55. 55. Differences in strains <ul><li>P. malariae </li></ul><ul><ul><li>No dormant stage </li></ul></ul><ul><ul><li>Single signet ring trophs per cell </li></ul></ul><ul><ul><li>Very low parasitemia </li></ul></ul>www.freelivedoctor.com
  56. 56. Treatment <ul><li>P. falciparum malaria can be fatal if not promptly diagnosed and treated </li></ul><ul><li>Non- P. falciparum malaria rarely requires hospitalization </li></ul><ul><li>Widespread drug resistance dictates regimen ( www.cdc.gov/travel ; CDC malaria hot line: 770-488-7788). </li></ul>www.freelivedoctor.com
  57. 57. Treatment Uncomplicated malaria <ul><li>P. vivax, ovale, malariae, chloroquine-susceptible falciparum </li></ul><ul><ul><li>Chloroquine </li></ul></ul><ul><ul><li>Primaquine for dormant liver forms </li></ul></ul><ul><li>Chloroquine-resistant falciparum </li></ul><ul><ul><li>Quinine plus doxycycline </li></ul></ul><ul><ul><li>Mefloquine </li></ul></ul><ul><ul><li>Atovaquone plus proguanil (AP) </li></ul></ul><ul><ul><li>Artemisins (common in SE Asia due to multi-drug resistance) </li></ul></ul>www.freelivedoctor.com
  58. 58. Treatment Severe malaria <ul><li>Drug options </li></ul><ul><ul><li>Quinidine gluconate—only approved parenteral agent in US </li></ul></ul><ul><ul><li>Artemisin </li></ul></ul>www.freelivedoctor.com
  59. 59. Prevention <ul><li>Mefloquine </li></ul><ul><li>Doxycycline </li></ul><ul><li>Nets </li></ul><ul><li>30-35% DEET </li></ul><ul><li>Permethrin spray for clothing and nets </li></ul>www.freelivedoctor.com
  60. 60. And don’t forget baggage malaria! www.freelivedoctor.com
  61. 61. Case 5 <ul><li>Mrs. R. was treated with IV quinidine and improved rapidly. </li></ul><ul><li>In retrospect, Mr. R. had died from untreated blackwater fever </li></ul><ul><ul><li>Few parasites in peripheral blood </li></ul></ul><ul><ul><li>Acute renal failure </li></ul></ul>www.freelivedoctor.com
  62. 62. Case 6 <ul><li>A 24-year-old white male army officer </li></ul><ul><li>Referred to the VA ID clinic with a 3-month history of a lesion on his right leg, developing approximately 2 weeks after returning from Iraq </li></ul><ul><li>Recent travel history: 1 month in Kuwait and 2 months traveling between Kuwait and Iraq </li></ul><ul><li>Recalled being bitten numerous times by small flying insects and other nasty “bugs” </li></ul>www.freelivedoctor.com
  63. 63. Case 6 <ul><li>Physical examination essentially normal except for: </li></ul><ul><li>Non-tender (20 × 15 mm) scaly erythematous plaque with a moist central erosion of the left popliteal area. </li></ul><ul><li>There was no lymphadenopathy and no mucosal lesions were noted </li></ul>www.freelivedoctor.com
  64. 64. www.freelivedoctor.com
  65. 65. Diagnosis? www.freelivedoctor.com
  66. 66. www.freelivedoctor.com
  67. 67. An intact macrophage practically filled with amastigotes (arrows), www.freelivedoctor.com
  68. 68. Leishmaniasis <ul><li>Tropical areas where phlebotomine sandfly is common: South America, India, Bangladesh, Middle East, East Africa </li></ul><ul><li>Sandfly introduces flagellated promastigote into human  ingested by macrophages  develops into nonflagellated amastigote </li></ul>www.freelivedoctor.com
  69. 69. Leishmaniasis <ul><li>Cutaneous </li></ul><ul><ul><li>Most common among farmers, settlers, troops and tourists in Mid East (L. major and tropica), Central and South America (L. mexicana, braziliensis, amazonensis, and panamensis) </li></ul></ul><ul><ul><li>L. mexicana reported in Texas </li></ul></ul><ul><li>Visceral (kala azar) </li></ul><ul><ul><li>Anemia, leukopenia, thrombocytopenia, hypergammaglobulinemia common </li></ul></ul>www.freelivedoctor.com
  70. 70. Leishmaniasis: Diagnosis <ul><li>Biopsy and Giemsa stain with amastigotes </li></ul><ul><li>Species most prevalent in different places </li></ul><ul><ul><ul><ul><li>L. donovani – India </li></ul></ul></ul></ul><ul><ul><ul><ul><li>L. infantum – Mid East </li></ul></ul></ul></ul><ul><ul><ul><ul><li>L. chagasi – Latin America </li></ul></ul></ul></ul><ul><ul><ul><ul><li>L. amazonensis -- Brazil </li></ul></ul></ul></ul>www.freelivedoctor.com
  71. 71. Visceral Leishmaniasis <ul><li>Dissemination of amastigotes throughout the reticulendothelial system of the body </li></ul><ul><ul><li>Spleen </li></ul></ul><ul><ul><li>Bone marrow </li></ul></ul><ul><ul><li>Lymph nodes </li></ul></ul><ul><li>Opportunistic infection in AIDS patients </li></ul><ul><li>Ineffective humeral response </li></ul>www.freelivedoctor.com
  72. 72. Hepatosplenomegaly www.freelivedoctor.com
  73. 73. Splenic aspirate <ul><li>Most satisfactory method </li></ul><ul><li>Spleen must be at least 3cm below LCM </li></ul><ul><li>Aspirate stained with Giemsa </li></ul>www.freelivedoctor.com
  74. 74. Leishmaniasis: treatment <ul><li>Only drug approved in US is Amphotericin B </li></ul><ul><li>Treatment of cutaneous disease depends on anatomic location </li></ul><ul><li>Many spontaneously heal and do not require treatment </li></ul>www.freelivedoctor.com
  75. 75. www.freelivedoctor.com
  76. 76. Remember.. <ul><li>The factors determining the form of leishmaniasis: </li></ul><ul><ul><li>Leishmanial species </li></ul></ul><ul><ul><li>Geographic location </li></ul></ul><ul><ul><li>Immune response of the host </li></ul></ul>www.freelivedoctor.com
  77. 77. Case 7 <ul><li>38-year-old businessman </li></ul><ul><li>Previously fit </li></ul><ul><li>2-week history of fever since returning from Brazil business trip </li></ul><ul><li>Flu-like symptoms and myalgia </li></ul><ul><li>Had consumed steak tartare in Brazil </li></ul><ul><li>Results all unremarkable---normal WBC and ESR; negative smears; CXR and urine OK </li></ul><ul><li>Continued to have fever, tachycardia and myalgia </li></ul>www.freelivedoctor.com
  78. 78. Case 8 <ul><li>A 29-yr-old man with AIDS (CD4 count=59) presents with a 2 week history of headache, fevers and new onset seizures </li></ul><ul><li>He had not been taking any antiretroviral medications </li></ul>www.freelivedoctor.com
  79. 79. Cases 7 & 8 <ul><li>What parasite could </li></ul><ul><li>cause this picture? </li></ul>www.freelivedoctor.com
  80. 80. AIDS Patient www.freelivedoctor.com
  81. 81. AIDS Patient www.freelivedoctor.com
  82. 82. Toxoplasma gondii cyst in brain tissue with H & E stain (100x) www.freelivedoctor.com
  83. 83. For the businessman… <ul><li>Toxoplasma serology was positive at a very high titer </li></ul><ul><li>Responded to treatment with sulphonamide + pyrimethamine </li></ul><ul><li>No relapse </li></ul>www.freelivedoctor.com
  84. 84. Transmission <ul><li>Eating oocysts excreted by cats harboring sexual stages of parasite </li></ul><ul><li>Outbreaks traced to inadequately cooked meat of herbivores (raw beef) </li></ul><ul><li>Mutton </li></ul>www.freelivedoctor.com
  85. 85. Toxoplasma gondii <ul><li>Worldwide distribution </li></ul><ul><li>Human infection </li></ul><ul><ul><li>Ingestion of cysts in undercooked meat of herbivores </li></ul></ul><ul><ul><li>Water/food contaminated with oocysts </li></ul></ul><ul><ul><li>Congenitally </li></ul></ul><ul><ul><li>Infected organs, blood (less common) </li></ul></ul><ul><li>Prevalence of latent infection in US about 10%; France about 75% </li></ul><ul><ul><li>Generally higher in less-developed world </li></ul></ul><ul><ul><li>50% in AIDS patients; up to 90% of AIDS patients in developing world </li></ul></ul>www.freelivedoctor.com
  86. 86. Toxoplasma gondii: Immunocompetent hosts <ul><li>Latent infection (persistence of cysts) is generally asymptomatic </li></ul><ul><li>Cervical lymphadenopathy (10-20%) </li></ul><ul><li>Mono-like presentation (<1% of all mono-like illnesses) </li></ul><ul><li>Chorioretinitis </li></ul><ul><li>Very rare: myocarditis, myositis </li></ul>www.freelivedoctor.com
  87. 87. Toxoplasma gondii: Immunocompromised hosts <ul><li>Often life-threatening </li></ul><ul><li>Almost always reactivation of latent infection </li></ul><ul><li>AIDS </li></ul><ul><ul><li>Encephalitis most common manifestation </li></ul></ul><ul><ul><li>Usually subacute onset/focal (if CD4< 200) </li></ul></ul><ul><ul><li>Mental status changes, seizures, weakness, cranial nerve abnormalities, cerebellar signs, </li></ul></ul><ul><ul><li>Can present as acute hemiparesis/language deficit </li></ul></ul><ul><ul><li>Usually multiple ring-enhancing lesions on CT/MRI </li></ul></ul><ul><li>Pneumonitis </li></ul><ul><li>Chorioretinitis </li></ul>www.freelivedoctor.com
  88. 88. Toxoplasma gondii: Clinical manifestations <ul><li>Immunocompromised hosts </li></ul><ul><ul><li>Non-AIDS (transplants, hematologic malignancies) </li></ul></ul><ul><ul><ul><li>CNS 75% </li></ul></ul></ul><ul><ul><ul><li>Myocardial 40% </li></ul></ul></ul><ul><ul><ul><li>Pulmonary 25% </li></ul></ul></ul>www.freelivedoctor.com
  89. 89. Toxoplasma gondii: Clinical manifestations <ul><li>Congenital </li></ul><ul><li>Acute infection asymptomatic in mother </li></ul><ul><li>Clinical manifestations range: no sequelae to sequelae that develop at various times after birth </li></ul><ul><ul><li>Chorioretinitis </li></ul></ul><ul><ul><li>Strabismus </li></ul></ul><ul><ul><li>Blindness </li></ul></ul><ul><ul><li>Epilepsy, mental retardation, pneumonitis, microcephaly, hydrocephalus, spontaneous abortion, stillbirth </li></ul></ul>www.freelivedoctor.com
  90. 90. Toxoplasma gondii: diagnosis <ul><li>Clinical suspicion crucial </li></ul><ul><li>Serology is primary method of diagnosis </li></ul><ul><ul><li>IgM, IgG </li></ul></ul><ul><li>Histopathology </li></ul><ul><ul><li>Tachyzoites in tissue sections or body fluid (difficult to stain) </li></ul></ul><ul><ul><li>Multiple cysts near necrotic, inflammatory lesions </li></ul></ul>www.freelivedoctor.com
  91. 91. Toxoplasma gondii: Treatment <ul><li>Immunocompetent adults are usually not treated unless visceral disease is overt or symptoms are severe and persistent </li></ul><ul><li>Immunodeficient patients </li></ul><ul><ul><li>Latent disease: not treated </li></ul></ul><ul><ul><li>Active disease: pyrimethamine + sulfadiazone + folinic acid </li></ul></ul>www.freelivedoctor.com
  92. 92. Toxoplasma gondii: Treatment <ul><li>Congenital: </li></ul><ul><ul><li>Treatment of acute infected pregnant women decreases but does not eliminate transmission </li></ul></ul><ul><ul><ul><li>Spiramycin </li></ul></ul></ul><ul><ul><li>If fetal infection is documented, treat with pyrimethamine + sulfadiazone + folinic acid </li></ul></ul><ul><ul><li>Postnatal treatment: pyrimethamine + sulfadiazone + folinic acid </li></ul></ul>www.freelivedoctor.com
  93. 93. Case 22 <ul><li>25-year-old Caucasian woman presented with 1-week history of fever, chills, sweating, myalgias, fatigue </li></ul><ul><li>No travel abroad </li></ul><ul><li>Had gone cranberry picking in Massachusetts approx 3 weeks earlier </li></ul><ul><li>PE: anemic, hepatosplenomegaly </li></ul><ul><li>Blood workup: hemolytic anemia, reduced platelets  </li></ul>www.freelivedoctor.com
  94. 94. Thick smear www.freelivedoctor.com
  95. 95. Thin smear Maltese cross www.freelivedoctor.com
  96. 96. Diagnosis?? www.freelivedoctor.com
  97. 97. Babesiosis <ul><li>Babesiosis caused by hemoprotozoan parasites of the genus Babesia </li></ul><ul><li>> 100 species reported </li></ul><ul><li>Few actually cause human infection </li></ul>www.freelivedoctor.com
  98. 98. Babesiosis <ul><li>Babesia microti </li></ul><ul><li>Life cycle involves two hosts: </li></ul><ul><ul><li>Deer tick, Ixodes dammini, (definitive host) introduces sporozoites into white-footed mouse </li></ul></ul><ul><li>Once ingested by an appropriate tick gametes unite and undergo a sporogonic cycle resulting in sporozoites </li></ul><ul><li>Humans enter cycle when bitten by infected ticks </li></ul>www.freelivedoctor.com
  99. 99. Babesiosis <ul><li>Deer are the hosts upon which the adult ticks feed and are indirectly part of the Babesia cycle as they influence the tick population </li></ul>www.freelivedoctor.com
  100. 100. Babesiosis <ul><li>Clindamycin* plus quinine </li></ul><ul><li>Atovaquone* plus azithromycin* </li></ul><ul><li>Exchange transfusion in severely ill patients with high parasitemia </li></ul><ul><li>* Approved by FDA </li></ul>www.freelivedoctor.com
  101. 101. Case 9 <ul><li>6-year-old son of seasonal farm worker </li></ul><ul><li>Presents with cough and fever, wheeze </li></ul><ul><li>CXR reveals a lobar pneumonia </li></ul><ul><li>Admitted for initial therapy </li></ul><ul><li>After 2 days of antibiotics, with good defervescence, a worm is found in his bed </li></ul><ul><li>Stool exam reveals … </li></ul>www.freelivedoctor.com
  102. 102. www.freelivedoctor.com
  103. 103. Diagnosis? www.freelivedoctor.com
  104. 104. Ascaris lumbricoides <ul><li>In GI tract, few symptoms in light infections </li></ul><ul><ul><li>Nausea </li></ul></ul><ul><ul><li>Vomiting </li></ul></ul><ul><ul><li>Obstruction of small bowel or common bile duct. </li></ul></ul><ul><li>Pulmonary: symptoms due to migration </li></ul><ul><ul><li>Alveoli (verminous pneumonia)—cough, fever wheeze, dyspnea, X-ray changes, eosinophilia </li></ul></ul>www.freelivedoctor.com
  105. 105. Effects of Adult Ascaris Worms <ul><li>Depends on worm load </li></ul><ul><li>Effects </li></ul><ul><ul><li>Mechanical: obstruction, volvulus, intussusception, appendicitis, obstructive jaundice, liver abscesses, pancreatitis, asphyxia </li></ul></ul><ul><li>Toxic and Metabolic </li></ul><ul><ul><li>Malnutrition (complex) </li></ul></ul>www.freelivedoctor.com
  106. 106. Ascaris lumbricoides Diagnosis <ul><li>Characteristic eggs on direct smear examination </li></ul><ul><li>If treating mixed infections, treat Ascaris first </li></ul><ul><ul><li>Mebendazole </li></ul></ul><ul><ul><li>Pyrantel </li></ul></ul><ul><li>Control: </li></ul><ul><ul><li>Periodic mass treatment of children, health education, environmental sanitation </li></ul></ul>www.freelivedoctor.com
  107. 107. www.freelivedoctor.com
  108. 108. Case 10 <ul><li>11-year-old female </li></ul><ul><li>Doing poorly in school </li></ul><ul><li>Not sleeping well </li></ul><ul><li>Anorectic </li></ul><ul><li>Complains of itching in rectal region throughout the day </li></ul><ul><li>A Scotch-tape test reveals… </li></ul>www.freelivedoctor.com
  109. 109. www.freelivedoctor.com
  110. 110. www.freelivedoctor.com
  111. 111. www.freelivedoctor.com
  112. 112. Diagnosis? www.freelivedoctor.com
  113. 113. Enterobius (Pinworm) <ul><li>18 million infections in U.S. </li></ul><ul><li>Incidence higher in whites </li></ul><ul><li>Preschool and elementary school most often </li></ul><ul><li>Mostly asymptomatic </li></ul><ul><li>Nocturnal anal pruritis cardinal feature due to migration and eggs </li></ul><ul><li>May have insomnia, possible emotional symptoms </li></ul><ul><li>DS-eggs or adults on perineum {scotch tape} </li></ul><ul><li>Mebendazole 100 mg. Repeat in 2 weeks. Pyrantel pamoate 11 mg/kg; repeat 2 weeks </li></ul>www.freelivedoctor.com
  114. 114. <ul><li>69-year-old male was admitted to VA Hospital </li></ul><ul><li>Far East Prisoner of War (FEPOW) </li></ul><ul><li>COPD--steroids for 3 years </li></ul><ul><li>2-month history of nausea, vomiting and anorexia </li></ul><ul><li>25 pounds weight loss </li></ul>Case 11 www.freelivedoctor.com
  115. 115. On the day of admission… <ul><li>Fever, confusion, and not able to get out of bed---transported to the hospital </li></ul><ul><li>Initial blood work: </li></ul><ul><ul><li>Elevated WBC </li></ul></ul><ul><ul><li>Raised eosinophil count 4 times normal </li></ul></ul><ul><li>Underwent UGI endoscopy </li></ul><ul><li>Duodenal biopsy obtained </li></ul>www.freelivedoctor.com
  116. 116. www.freelivedoctor.com
  117. 117. Diagnosis www.freelivedoctor.com
  118. 118. Strongyloides: Crucial Aspects of Life Cycle <ul><li>Infection acquired through penetration of intact skin </li></ul><ul><li>Infection may persist for many years via autoinfection </li></ul><ul><li>In immunocompromised patients, there is risk of dissemination or hyperinfection </li></ul><ul><ul><li>Hyperinfection syndrome </li></ul></ul>www.freelivedoctor.com
  119. 119. Disseminated Strongyloidiasis <ul><li>High mortality  75% </li></ul><ul><li>Penetration of gut wall by infective larvae </li></ul><ul><li>Gut organisms carried on the surface of larvae results in polymicrobial sepsis, meningitis </li></ul><ul><li>Larvae disseminate into all parts of body: CNS, lungs, bladder, peritoneum </li></ul>www.freelivedoctor.com
  120. 120. Summary—Clinical Findings <ul><li>Defective cell-meditated immunity: steroids, burns, lymphomas, AIDS (?) </li></ul><ul><li>Gl symptoms in about two-thirds: </li></ul><ul><ul><li>Abdominal pain </li></ul></ul><ul><ul><li>Bloating </li></ul></ul><ul><ul><li>Diarrhea </li></ul></ul><ul><ul><li>Constipation </li></ul></ul><ul><li>Wheezing, SOB, hemoptysis </li></ul>www.freelivedoctor.com
  121. 121. Summary—Clinical Findings <ul><li>Skin rash or pruritis in ~ one-third </li></ul><ul><ul><li>Larva currens (racing larva) </li></ul></ul><ul><ul><li>Intensely pruritic </li></ul></ul><ul><ul><li>Linear or serpiginous urticaria with flare that moves 5-15 cm/hr </li></ul></ul><ul><ul><li>Usually buttocks, groin, and trunk </li></ul></ul><ul><ul><li>In dissemination, diffuse petechiae and purpura </li></ul></ul>www.freelivedoctor.com
  122. 122. Summary-Clinical Findings <ul><li>Eosinophilia 60-95% </li></ul><ul><li>Less if on steroids </li></ul>www.freelivedoctor.com
  123. 123. Case 12 <ul><li>57 year old farmer from Dixie County </li></ul><ul><li>Presents with profound SOB </li></ul><ul><li>Physical examination: anemic otherwise unremarkable </li></ul><ul><li>Laboratory examination reveals a profound anemia (hct 24) with aniso and poikilocytosis </li></ul><ul><li>Remainder of laboratory examination normal. </li></ul>www.freelivedoctor.com
  124. 124. www.freelivedoctor.com
  125. 125. Diagnosis? www.freelivedoctor.com
  126. 126. www.freelivedoctor.com
  127. 127. Hookworm <ul><li>Hookworm responsible for development of USPHS </li></ul><ul><li>Caused by two different species (North American and Old World) </li></ul><ul><li>Very similar to strongyloides in life cycle </li></ul><ul><li>Attaches to duodenum, feeds on blood </li></ul><ul><li>Elaborates anticoagulant, attaches and reattaches many times </li></ul><ul><li>Loss of around 0.1 ml/d of blood per worm </li></ul>www.freelivedoctor.com
  128. 128. www.freelivedoctor.com
  129. 129. www.freelivedoctor.com
  130. 130. Case 13 <ul><li>8-yr-old schoolgirl visiting the U.S. from Malaysia </li></ul><ul><li>1 week history of epigastric pain, flatulence, anorexia, bloody diarrhea </li></ul><ul><li>No eosinophilia noted </li></ul><ul><li>Clinical diagnosis of amoebic dysentery made </li></ul><ul><li>However, microscopy of stool prep… </li></ul>www.freelivedoctor.com
  131. 131. www.freelivedoctor.com
  132. 132. Diagnosis? www.freelivedoctor.com
  133. 133. Trichuris trichiura (Whipworm) <ul><li>Common in Southeast U.S. </li></ul><ul><li>Frequently coexists with ascaris </li></ul><ul><li>Entirely intraluminal life cycle—eggs are ingested </li></ul><ul><li>Frequently asymptomatic </li></ul><ul><li>Severe infections: diarrhea, abdominal pain and tenesmus </li></ul><ul><li>Rectal prolapse in children </li></ul><ul><li>DS-eggs in stool </li></ul><ul><li>Mebendazole 100 mg bid x 3 days </li></ul>www.freelivedoctor.com
  134. 134. www.freelivedoctor.com
  135. 135. www.freelivedoctor.com
  136. 136. www.freelivedoctor.com
  137. 137. Case 14 <ul><li>18-year-old trailer park handyman seen in ER </li></ul><ul><li>Worked under trailers wearing shorts and no shirt </li></ul><ul><li>Developed intensely pruritic skin rash </li></ul><ul><li>Unable to sleep </li></ul><ul><li>WBC 18,000 </li></ul><ul><li>65% eosinophils. </li></ul>www.freelivedoctor.com
  138. 138. www.freelivedoctor.com
  139. 139. Case 15 <ul><li>An 8 year old boy </li></ul><ul><li>Presents with skin lesions and itching after spending the summer at a beach condo in St. Augustine with his family (mother, father, younger sister, dog and cat). </li></ul><ul><li>Legs show several raised, reddened, serpiginous lesions that are intensely pruritic. </li></ul>www.freelivedoctor.com
  140. 140. www.freelivedoctor.com
  141. 141. Diagnosis ? www.freelivedoctor.com
  142. 142. Cutaneous Larva Migrans <ul><li>Caused by filariform larvae of dog or cat hookworm ( Ancylostoma braziliense or Ancylostoma duodenale </li></ul><ul><li>Common in Southeast U.S. </li></ul><ul><li>Red papule at entry with serpiginous tunnel </li></ul><ul><li>Intense pruritis </li></ul><ul><li>Self limiting condition </li></ul><ul><li>Diagnosis clinical </li></ul><ul><li>Topical or oral thiabendazole 25 mg/kg bid for 3-5 days </li></ul><ul><li>May use ethyl chloride topically </li></ul>www.freelivedoctor.com
  143. 143. Cutaneous larva migrans (creeping eruption) <ul><li>More common in children </li></ul><ul><ul><li>Larvae penetrate skin and cause tingling followed by intense itching. </li></ul></ul><ul><li>Eggs shed from dog and cat bowels develop into infectious larvae outside the body in places protected from desiccation and extremes of temperature </li></ul><ul><li>Shady, sandy areas under houses, at beach, etc. </li></ul>www.freelivedoctor.com
  144. 144. Cutaneous larva migrans (creeping eruption) <ul><ul><li>Usually not associated with systemic symptoms </li></ul></ul>www.freelivedoctor.com
  145. 145. Cutaneous larva migrans (creeping eruption) <ul><li>Diagnosis and treatment </li></ul><ul><li>Skin lesions are readily recognized </li></ul><ul><li>Usually diagnosed clinically </li></ul><ul><li>Generally do not require biopsy </li></ul><ul><ul><ul><ul><li>Reveal eosinophilia inflammatory infiltrate </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Migrating parasite is generally not seen </li></ul></ul></ul></ul><ul><li>Stool smear will reveal eggs </li></ul>www.freelivedoctor.com
  146. 146. www.freelivedoctor.com
  147. 147. www.freelivedoctor.com
  148. 148. Visceral Larva Migrans <ul><li>Infection with dog or cat round worms </li></ul><ul><li>Toxocara canis; Toxocara catis </li></ul><ul><li>Underdiagnosed based on seroprevalence surveys </li></ul><ul><li>Heavy infections associated with fever, cough, nausea, vomiting, hepatomegaly, and eosinophilia </li></ul><ul><li>Uncommon in adults </li></ul><ul><li>Ocular type more common in adults </li></ul><ul><li>Diagnosis-ELISA </li></ul><ul><li>Thiabendazole: 25 mg/kg bid X 5 days </li></ul>www.freelivedoctor.com
  149. 149. Case 17 <ul><li>A 34 yr-old woman from Saudi Arabia </li></ul><ul><li>Radiation and cyclophosphamide, adriamycin, vincristine and prednisone for diffuse large B cell lymphoma of the neck. </li></ul><ul><li>Mild eosinophilia (AEC=500) at the time of diagnosis </li></ul><ul><li>4 months after initiation of chemo, c/o intermittent diffuse abdominal pain, bloating, constipation and occasional rectal bleeding. </li></ul><ul><li>Absolute eosinophil count: 1000 </li></ul>www.freelivedoctor.com
  150. 150. Case 17 <ul><li>No evidence of lymphoma found on re-staging </li></ul><ul><li>Completed chemo, was deemed to be in complete remission, but had persistence of GI complaints. </li></ul><ul><li>Upper endoscopy was unrevealing. </li></ul><ul><li>Colonoscopy and biopsy revealed granulomatous inflammation, prominent eosinophilic infiltrate, surrounding a collection of eggs. </li></ul>www.freelivedoctor.com
  151. 151. www.freelivedoctor.com
  152. 152. Chronic intestinal schistosomiasis www.freelivedoctor.com
  153. 153. Case 17 <ul><li>The patient was treated with praziquantel and did not have relapse of symptoms at 2-year follow-up </li></ul><ul><li>AEC=250 </li></ul>www.freelivedoctor.com
  154. 154. Schistosomiasis: Epidemiology and life cycle <ul><li>Cercariae in fresh water penetrate human skin. </li></ul><ul><li>Cercariae mature to schistosomulae, which enter the bloodstream, liver and lung. </li></ul><ul><li>Mature worms migrate to the venous system of the small intestine ( S. japonicum ), large intestine ( S. mansoni ) or bladder venous plexus ( S. haematobium ). </li></ul>www.freelivedoctor.com
  155. 155. Schistosomiasis: Epidemiology and life cycle <ul><li>Worms release eggs for many years into stool or urine, resulting in fresh water contamination. </li></ul><ul><li>Freshwater snails are infected by miracidia and are necessary for the production of cercariae and human infection. </li></ul><ul><li>S. mansoni </li></ul><ul><ul><li>South America, Caribbean, Africa, Mid East </li></ul></ul><ul><li>S. japonicum </li></ul><ul><ul><li>China and Philippines </li></ul></ul><ul><li>S. haematobium </li></ul><ul><ul><li>Africa, Mid East </li></ul></ul>www.freelivedoctor.com
  156. 156. Schistosomiasis: Clinical manifestations <ul><li>Three stages of disease, corresponding to life cycle within human hosts </li></ul><ul><li>Swimmer’s itch </li></ul><ul><ul><li>Within 24 hours of cercariae penetration </li></ul></ul><ul><li>Serum sickness syndrome (Katayama fever) </li></ul><ul><ul><li>4 to 8 weeks later when worms mature and release eggs </li></ul></ul><ul><ul><ul><li>Fever, headache, cough, chills, sweating, lymphadenopathy, hepatosplenomegaly  usually resolves spontaneously </li></ul></ul></ul><ul><ul><ul><li>Elevated IgE and eosinophils </li></ul></ul></ul><ul><ul><ul><li>Most common with S. japonicum </li></ul></ul></ul>www.freelivedoctor.com
  157. 157. Chronic Schistosomiasis <ul><li>Granulomatous reaction to egg deposition in intestine, liver, bladder, lungs </li></ul><ul><li>S. mansoni, japonicum </li></ul><ul><ul><li>Chronic diarrhea, abdominal pain, blood loss, portal hypertension, hepatosplenomegaly, pulmonary hypertension </li></ul></ul><ul><ul><li>Eosinophilia is common </li></ul></ul><ul><ul><li>Liver function tests are usually normal </li></ul></ul><ul><li>S. Haematobium </li></ul><ul><ul><li>Hematuria, bladder obstruction, hydronephrosis, recurrent UTIs, bladder cancer </li></ul></ul>www.freelivedoctor.com
  158. 158. Schistosomiasis: Diagnosis and Treatment <ul><li>Detection of characteristic eggs in stool, urine or tissue biopsy is diagnostic </li></ul><ul><ul><li>Urine is best between 12N and 2Pm, passed through 10 µm filter to concentrate eggs </li></ul></ul><ul><li>Antibody tests are available, but limited by sensitivity, specificity </li></ul><ul><li>Praziquantel is the drug of choice </li></ul>www.freelivedoctor.com
  159. 159. www.freelivedoctor.com
  160. 160. S. mansoni Stool S. haematobium Urine S. japonicum www.freelivedoctor.com
  161. 161. Case 18 <ul><li>15-yr-old girl </li></ul><ul><li>Fever, rash, swelling around the eye and hands, severe headaches </li></ul><ul><li>Fatigue, aching muscles and joints </li></ul><ul><li>Swollen lymph nodes on the back of neck </li></ul><ul><li>Weight loss </li></ul><ul><li>Progressive confusion, personality changes </li></ul><ul><li>Sleeping for long periods of the day </li></ul><ul><li>Insomnia </li></ul><ul><li>Had been on a safari with parents to West Africa </li></ul><ul><li>Dusky red lesion developed within 1 week </li></ul><ul><li>Vaguely remembered being bitten by a fly </li></ul>www.freelivedoctor.com
  162. 162. Diagnosis? www.freelivedoctor.com
  163. 163. Investigations <ul><li>Blood films </li></ul><ul><li>Lumbar puncture </li></ul>www.freelivedoctor.com
  164. 164. Blood smear www.freelivedoctor.com
  165. 165. African trypanosomiasis Trypanosoma brucei gambiense www.freelivedoctor.com
  166. 166. Tsetse fly www.freelivedoctor.com
  167. 167. Treatment <ul><li>Suramin </li></ul><ul><li>Melasoprol </li></ul>www.freelivedoctor.com
  168. 168. Case 19 <ul><li>6-yr-old boy recently arrived from Brazil </li></ul><ul><li>Swelling around the eye </li></ul><ul><li>Conjunctivitis </li></ul><ul><li>Fever </li></ul><ul><li>Enlarged lymph nodes </li></ul><ul><li>Hepatosplenomegaly </li></ul><ul><li>Had stayed in a hotel—adobe style with thatched roof </li></ul>www.freelivedoctor.com
  169. 169. www.freelivedoctor.com
  170. 170. Diagnosis? www.freelivedoctor.com
  171. 171. Blood smear www.freelivedoctor.com
  172. 172. Reduviid bug (assassin bug) www.freelivedoctor.com
  173. 173. Chagas disease: Clinical manifestations <ul><li>Local edema is followed by fever, malaise, anorexia </li></ul><ul><ul><li>More rarely: myocarditis, encephalitis </li></ul></ul><ul><li>Years later: chronic Chagas Disease (10-30%) </li></ul><ul><ul><li>Heart: primary target </li></ul></ul><ul><ul><ul><li>Cardiomyopathy associated with CHF, emboli, arrythmias </li></ul></ul></ul><ul><ul><li>GI tract: mega-esophagus, megacolon </li></ul></ul>www.freelivedoctor.com
  174. 174. Chagas disease: Diagnosis and treatment <ul><li>Acute disease is diagnosed by seeing trypomastigotes on peripheral blood smear </li></ul><ul><li>Chronic disease is diagnosed by ELISA detecting IgG antibody to T. cruzi </li></ul><ul><li>Treatment slows the progression of heart disease </li></ul>www.freelivedoctor.com
  175. 175. Chagas Disease <ul><li>Public health implications in the US </li></ul><ul><li>Chronic </li></ul><ul><ul><li>Cardiomyopathy </li></ul></ul><ul><ul><li>Megaesophagus </li></ul></ul><ul><ul><li>Megacolon </li></ul></ul><ul><li>Blood transfusion </li></ul><ul><li>Transplant </li></ul><ul><ul><li>Solid organ </li></ul></ul><ul><ul><li>Musculoskeletal allograft tissue </li></ul></ul>www.freelivedoctor.com
  176. 176. Case 20 <ul><li>20-yr-old male </li></ul><ul><li>Abdominal pain and nausea for several months </li></ul><ul><li>More common in the morning </li></ul><ul><li>Relieved by eating small amounts of food </li></ul><ul><li>Some diarrhea and irritability </li></ul><ul><li>Weight loss </li></ul><ul><li>Pruritus ani </li></ul><ul><li>Passage of white “bits” </li></ul>www.freelivedoctor.com
  177. 177. www.freelivedoctor.com
  178. 178. Diagnosis? www.freelivedoctor.com
  179. 179. Taenia saginata <ul><li>Ingestion of raw or poorly cooked beef </li></ul><ul><li>Cows infected via the ingestion of human waste containing the eggs of the parasite </li></ul><ul><li>Cows contain viable cysticercus larvae in the muscle </li></ul><ul><li>Humans act as the host only to the adult tapeworms </li></ul><ul><li>Up to 25 meters in the lumen of intestine </li></ul><ul><li>Found all over the world, including the U.S. </li></ul>www.freelivedoctor.com
  180. 180. Beef Tapeworm www.freelivedoctor.com
  181. 181. Treatment <ul><li>Praziquantel </li></ul><ul><li>Albendazole </li></ul><ul><li>Niclosamide </li></ul>www.freelivedoctor.com
  182. 182. Tapeworms (Cestodes) <ul><li>Adult worms inhabit GI tract of definitive vertebrate host </li></ul><ul><li>Larvae inhabit tissues of intermediate host </li></ul><ul><li>Humans </li></ul><ul><ul><li>Definitive for T. saginata </li></ul></ul><ul><ul><li>Intermediate for Echinococcus granulosus (hydatid) </li></ul></ul><ul><ul><li>Both definitive and intermediate for T. solium </li></ul></ul><ul><li>Adult worms shed egg-containing segments in stool ingested by intermediate host larval form in tissues </li></ul>www.freelivedoctor.com
  183. 183. Case 21 <ul><li>A 33 year-old Indian man was admitted with a grand mal seizure </li></ul><ul><li>2 yrs PTA, he had vertigo and CT revealed an enhancing calcified lesion in left temporal-parietal region </li></ul><ul><li>FHx: Brother had grand mal seizure several years earlier </li></ul><ul><li>Throughout his life, he has eaten a diet heavy in pork </li></ul>www.freelivedoctor.com
  184. 184. Case 21 <ul><li>Difficulty speaking and loss of consciousness while on the phone </li></ul><ul><li>Co-workers noticed generalized tonic-clonic seizures lasting 10 minutes. </li></ul><ul><li>CT revealed new localized edema around the previously identified lesion and a second contiguous ring enhancing lesion. </li></ul><ul><li>He received phenytoin (Dilantin, an antiseizure med) and 5 days of corticosteroids. </li></ul>www.freelivedoctor.com
  185. 185. www.freelivedoctor.com
  186. 186. Case 21 <ul><li>ELISA titer was positive for antibodies against Taenia solium. </li></ul><ul><li>The neurosurgeons tell you that resection is impossible because of the extent and location of the lesion </li></ul>www.freelivedoctor.com
  187. 187. Cystercercosis <ul><li>Human infected with the larval stage of Taenia solium </li></ul><ul><li>Humans can serve as definitive or intermediate host </li></ul><ul><li>Eggs are ingested, or possibly get to stomach by reverse peristalsis </li></ul><ul><li>Probably much more common than is reported, since most infections are asymptomatic </li></ul>www.freelivedoctor.com
  188. 188. Cystercercosis <ul><li>Symptoms depend on location of cysts, but frequently include motor spasms, seizures, confusion, irritability, and personality change </li></ul><ul><li>In the eye, often subretinal or in vitreous. Movement may be seen by the patient. Pain, amaurosis, and loss of vision may occur. </li></ul>www.freelivedoctor.com
  189. 189. Cysticercosis <ul><li>Clinical manifestations </li></ul><ul><ul><li>Adult worms rarely cause sxs </li></ul></ul><ul><ul><li>Larvae penetrate intestine, enter blood, and eventually encyst in the brain. </li></ul></ul><ul><ul><ul><li>Cerebral ventircles  hydrocephalus </li></ul></ul></ul><ul><ul><ul><li>Spinal cord  compression, paraplegia </li></ul></ul></ul><ul><ul><ul><li>Subarachnoid space  chronic meningitis </li></ul></ul></ul><ul><ul><ul><li>Cerebral cortex  seizures </li></ul></ul></ul><ul><ul><li>Cysts may remain asymptomatic for years, and become clinically apparent when larvae die </li></ul></ul><ul><ul><li>Larvae may encyst in other organs, but are rarely symptomatic </li></ul></ul>www.freelivedoctor.com
  190. 190. Cysticercosis <ul><li>Diagnosis </li></ul><ul><ul><li>CT and MRI preferred studies </li></ul></ul><ul><ul><ul><li>Discrete cysts that may enhance </li></ul></ul></ul><ul><ul><ul><li>Usually multiple lesions </li></ul></ul></ul><ul><ul><ul><ul><li>Single lesions especially common in cases from India </li></ul></ul></ul></ul><ul><ul><ul><li>Older lesions may calcify </li></ul></ul></ul><ul><ul><li>CSF </li></ul></ul><ul><ul><ul><li>Lymphs or eos, low glucose, elevated protein </li></ul></ul></ul><ul><ul><li>Serology </li></ul></ul><ul><ul><ul><li>Especially in cases with multiple cysts </li></ul></ul></ul>www.freelivedoctor.com
  191. 191. Cysticercosis <ul><li>Treatment </li></ul><ul><ul><li>Complex and controversial </li></ul></ul><ul><ul><li>Praziquantel and albendazole may kill cysts, but death of larvae can increase inflammation, edema and exacerbate sxs </li></ul></ul><ul><ul><li>When possible, surgical resection of symptomatic cyst is preferred </li></ul></ul><ul><ul><li>Corticosteroids vs. edema and inflammation; antiseizure meds </li></ul></ul>www.freelivedoctor.com
  192. 192. www.freelivedoctor.com
  193. 193. www.freelivedoctor.com
  194. 194. Case 21 <ul><li>He was not treated with praziquantel or albendazole </li></ul><ul><li>He continued to receive dilantin for seizures and was treated with corticosteroids for edema </li></ul>www.freelivedoctor.com
  195. 195. Classification of Parasitic Diseases <ul><li>Protozoa: amoeba; flagellates; ciliates </li></ul><ul><li>Metazoa (two phyla) </li></ul><ul><ul><li>Helminths (worms) </li></ul></ul><ul><ul><ul><li>Nematodes </li></ul></ul></ul><ul><ul><ul><ul><li>Intestinal </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Extra-intestinal </li></ul></ul></ul></ul><ul><ul><ul><li>Flatworms (platyhelminths) </li></ul></ul></ul><ul><ul><ul><ul><li>Cestodes (tapeworms) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Trematodes (flukes) </li></ul></ul></ul></ul><ul><ul><li>Arthopods (ectoparasites): scabies, lice, fly larvae </li></ul></ul>www.freelivedoctor.com
  196. 196. General rules of treatment <ul><li>Protozoa: require species-specific treatment </li></ul><ul><li>Metozoa: species-specific </li></ul>www.freelivedoctor.com
  197. 197. General rules of treatment of metazoa www.freelivedoctor.com Nematodes Intestinal Mebendazole or Albendazole Tissue Albendazole Filiariae Ivermectin, doxycycline Cestodes Praziquantel, Albendazole, Niclosamide Trematode Praziquantel Ectoparasites Permethrin, Ivermectin
  198. 198. This is just the beginning of a great adventure in infectious diseases Sine qua non : history and physical examination www.freelivedoctor.com
  199. 199. Thank you Lennox K. Archibald, MD, PhD, FRCP [email_address] www.freelivedoctor.com

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