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SEXUALLY TRANSMITTED INFECTIONS BASICS IN DIAGNOSIS

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SEXUALLY TRANSMITTED INFECTIONS BASICS IN DIAGNOSIS

SEXUALLY TRANSMITTED INFECTIONS BASICS IN DIAGNOSIS

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  • 1. SEXUALLY TRANSMITTED INFECTIONS BASICS IN DIAGNOSIS Dr.T.V.Rao MD Dr.T.V.Rao MD 1
  • 2. What are Sexually Transmitted Diseases • STD’s are infections that are spread from person to person through intimate sexual contact. • STD’s are dangerous because they are easily spread and it is hard to tell just by looking who has an STD. • 1 in 4 teenagers has an STD.(Western Statistics) Dr.T.V.Rao MD 2
  • 3. In North America The most commonly submitted sample is urine from women with acute or recurrent urinary tract infection. The most common cause of urinary tract infections in women is recent sexual activity. Tests for sexually transmitted infections are the second most commonly submitted samples send to medical laboratories. Dr.T.V.Rao MD 3
  • 4. Why STI Diagnosis is Important • • • • • STIs rapidly spread throughout communities. STIs can be associated with acute illness. STIs can be associated with chronic illness. STIs can be associated with remote illness. Ulcerative STI associated transmission of other illnesses, especially HIV. • Syphilis • Chancroid • LGV Dr.T.V.Rao MD 4
  • 5. Sexually Transmitted Infections • Bacterial • Yeasts and fungi – Candida albicans – Candida glabrata – Candida tropicalis – – – – Neisseria gonorrhoeae Chlamydia trachomatis Treponema pallidum Haemophilus ducreyi (Chancroid) – Lymphogranuloma – Mycoplasma • Parasites – Trichomonas Vaginalis • Viruses – – – – – – Entamoeba histolytica Herpes simplex II Hepatitis B Hepatitis C HIV Papillomavirus Dr.T.V.Rao MD 5
  • 6. Sexually Transmitted Infections • Neisseria gonorrhoeae • Chlamydia trachomatis • Treponema pallidum Dr.T.V.Rao MD 6
  • 7. F.H.C.-Hepatitis Acute tenosynovitis Sepsis Urethritis Neonatal Conjunctivitis Gonorrhea P.I.D. Chronic Arthritis Urethral Strictures Infertility Dr.T.V.Rao MD 7
  • 8. Hepatitis Acute Arthritis Urethritis Chlamydia trachomatis P.I.D. Neonatal Conjunctivitis Infertility Chronic Arthritis Dr.T.V.Rao MD 8
  • 9. Cardiovascular Gumma Lymphadenopathy Neurosyphilis Meningitis Tabes dorsalis General paresis Chancres Syphilis HIV Transmission. Chronic Arthritis Congenital Transmission Hepatitis Dr.T.V.Rao MD 9
  • 10. Test Procedures Requiring EQA (Those with Readily Available EQA Programs) • Neisseria gonorrhoeae – Gram stain – Culture – PCR • Chlamydia trachomatis – – – – DFA EIA PCR Culture • Treponema pallidum – Serological tests for Syphilis – VDRL, RPR, FTA-abs, MHA-tp Dr.T.V.Rao MD 10
  • 11. Diagnosis of Syphilis • The nontreponemal tests, VDRL and rapid plasma reagent (RPR), are antilipoidal antibodies seen in other disease states, pregnancy, and occasionally after vaccination. They are nonspecific and cannot rule in disease. These tests have sensitivities approaching 80% in patients with symptomatic primary syphilis and virtually 100% in patients with secondary syphilis. Dr.T.V.Rao MD 11
  • 12. Why quantification of VDRL / RPR tests • A positive VDRL/RPR should be quantified and titers followed at regular intervals after treatment. As such, its value is in response to treatment. However, it does not correlate with symptom resolution. • – Most patients have nonreactive nontreponemal tests within several years after successful treatment for syphilis, but a significant number have persistently positive tests, the so-called serofast reaction. Dr.T.V.Rao MD 12
  • 13. Laboratory Diagnosis • Identification of Treponema pallidum in lesions – Darkfield microscopy – Direct fluorescent antibody - T. pallidum (DFATP) • Serologic tests – Nontreponemal tests – Treponemal tests Dr.T.V.Rao MD 13
  • 14. Diagnosis Nontreponemal Serologic Tests (continued) Advantages: Disadvantages: • Rapid and inexpensive • Easy to perform and can be done in clinic or office • Quantitative • Used to follow response to therapy • Can be used to evaluate possible reinfection • May be insensitive in certain stages • False-positive reactions may occur • Prozone effect may cause a falsenegative reaction (rare) Dr.T.V.Rao MD 14
  • 15. Diagnosis • Patients with a reactive VDRL or RPR should have the result confirmed by specific treponemal testing. FTA-ABS and or EIA. • • Tertiary syphilis Serology is used in the diagnosis. Evaluation of neurosyphilis requires a lumbar puncture (LP) and evaluation of the CSF. • – The CDC currently recommends LP only if the patient is seroreactive and HIV positive, has symptoms of neurosyphilis Dr.T.V.Rao MD 15
  • 16. Tests to Confirm • Syphilis may be confirmed either via blood tests or direct visualization using microscopy. Typical diagnosis is with blood tests using nontreponemal and/or treponemal tests. Nontreponemal test are used initially and include venereal disease research laboratory (VDRL) and rapid plasma regain however as these test occasionally are falsely positive confirmation is required with a treponemal test such as treponemal pallidum particle agglutination (TPHA) or fluorescent treponemal antibody absorption test (FTAAbs) Dr.T.V.Rao MD 16
  • 17. VDRL - Background • The Venereal Disease Research Laboratory (VDRL) test is one of two variations of flocculation procedures used for serological testing of syphilis, the other being the Rapid Plasma Reagin (RPR). Flocculation testing is based on antibody detection with the interaction of soluble antigen with an antibody that results in a precipitate formation of fine particles. Dr.T.V.Rao MD 17
  • 18. VDRL Test Basics • The VDRL is a confirmatory serological micro flocculation slide test used for the detection of syphilis antibodies. In a VDRL procedure, the patient’s serum is heat-inactivated and mixed with a buffered saline suspension of VDRL Antigen containing cardiolipin, lecithin and cholesterol that binds with Reagin, an antibodylike protein. A combination of Reagin and VDRL Antigen form microscopic clumping called flocculation. Dr.T.V.Rao MD 18
  • 19. VDRL – A Standard Test for Syphilis • The VDRL can be used for qualitative and quantitative measurements and is recommended when a patient suspected of having syphilis has a negative dark field microscopy result or when atypical lesions are present. Dr.T.V.Rao MD 19
  • 20. VDRL Serological Procedure Principles • VDRL Antigen is a nontreponemal antigen composed of cardiolipin cholesterol and lecithin. The nontreponemal tests measures anti-lipid antibodies, which are formed by the host in response to lipids released from damaged host cells early in infection with T. pallidum, and lipid-like material form the treponemal cell surface. During syphilis infection, an antibody-like substance called reagin can be detected in the patient’s serum or CSF. Dr.T.V.Rao MD 20
  • 21. False Positive Reactions • Lupus erythematosus • Rheumatic fever • Vaccinia and virus pneumonia • Pneumococcal pneumonia • Infectious mononucleosis Dr.T.V.Rao MD • • • • Infectious hepatitis Leprosy Malaria Rheumatoid arthritis • Pregnancy • Aging individuals 21
  • 22. RPR test The RPR test is a nontreponemal testing procedure for the serologic detection of syphilis. Dr.T.V.Rao MD 22
  • 23. Principle of RPR Test • The RPR Card antigen suspension is a carbon particle cardiolipin antigen that detects reagin. • Reagin is an antibody like substance present in serum or plasma from individuals with syphilis. • The reagin binds to the test antigen which consists of cardiolipin-lecithin coated particles that cause macroscopic flocculation. Dr.T.V.Rao MD 23
  • 24. Principle of RPR • When a specimen such as serum or plasma contains antibody, flocculation occurs with the resulting aggregation of the carbon particles. • The flocculation appears as black clumps against the white background of the plastic coated card. Dr.T.V.Rao MD 24
  • 25. Principle of RPR • Antibodies associated with syphilis begin to appear in the blood 4 to 6 weeks after infection. Nontreponemal tests determine the presence of reagin. Reagin is a nontreponemal autoantibody directed against cardiolipin antigens. Dr.T.V.Rao MD 25
  • 26. Materials for RPR • RPR Test Cards • RPR Control Cards • RPR Antigen • Distilled Water • Dispenstirs • Rotator Dr.T.V.Rao MD 26
  • 27. RPR Test Background • The RPR test uses a white plastic coated card that consist of several circles that are 18 mm in diameter. • The controls which are strongly reactive, moderately reactive, and non-reactive are contained on the control card in a dried form. Dr.T.V.Rao MD 27
  • 28. Specimen Collection • Unheated Plasma specimen should be collected with an anticoagulant such as EDTA or heparin, plasma must be stored at 2 C to 8 C. Plasma must be tested within in 24 hrs. of collection Dr.T.V.Rao MD 28
  • 29. Specimen Processing *The addition of choline chloride, which inactivates complement enables the serum to be tested without prior heating. • Unheated serumcentrifuge for sedimentation of cellular elements, serum may be frozen until time of testing. • Heated Serum- transfer serum to clean tube and place in 56 C water bath for 30 minutes Dr.T.V.Rao MD 29
  • 30. Prepare the Card • Label rings on test card with numbers of samples to be tested • Use Dispenstir to draw up serum sample. • Hold Dispenstir in a perpendicular position directly over the test circle to which the specimen is to be delivered. • Squeeze Dispenstir to allow 1 drop to fall on to each circle Dr.T.V.Rao MD 30
  • 31. Performing the Test • Invert Dispenstir,and using the sealed end spread the specimen in the confines of the circle. • Reconstitute the antigen bottle, by shaking. Holding Dr.T.V.Rao MD 31
  • 32. Rotate card at Regulated Speed • Rotate card for 8 minutes on a mechanical rotator at 100 rpm. The test card she also be covered with a humidifier cover. • After rotating mechanically, the test card should be rotated manually by hand 3 to four rotations and then read immediately macroscopically in the “wet” state under a high intensity lamp. Dr.T.V.Rao MD 32
  • 33. Procedure for Controls • A. Use Dispensator to draw up distilled water • B. Drop 1 drop on the card test circle for each patient sample. • C. Invert Dispensator and spread the water in the circle until the dried control is completely reconstituted. • D. Add antigen as described for the patients • E. Rotate for 8 minutes at 100 rpm Dr.T.V.Rao MD 33
  • 34. Observe for Reactivity Dr.T.V.Rao MD 34
  • 35. Reactions of Controls The following reactions should be observed to compare against the test results:  Reactive control characteristic strong clumping.  Reactive moderate control moderate clumping.  Non-reactive control smooth, grayish appearance of unclumped particles Dr.T.V.Rao MD 35
  • 36. Repeat all Positive Samples after Dilutions Dr.T.V.Rao MD 36
  • 37. Explanation of Results • A negative RPR test may indicate one of the following: 1. The patient does not have syphilis. 2. The infection is too recent for antibodies to be produced. (Repeated tests should be administered at 1 week, 1 month, and 3 month intervals to establish presence or absence of disease). 3. The syphilis is latent or inactive 4. Faulty immunodefense mechanism 5. Faulty lab techniques Dr.T.V.Rao MD 37
  • 38. Explanation of Results • A positive reaction is not conclusive for syphilis. Several conditions produce biologic false positive results for syphilis. (False positive means that the test revealed a positive reaction when it was actually negative). • False positives may reveal the presence of other serious diseases. Dr.T.V.Rao MD 38
  • 39. Nontreponemal positive Tests Need Confirmation • Nontreponemal antigen tests are not entirely specific for syphilis and do not have satisfactory sensitivity in all stages of syphilis. Whenever the results of a nontreponemal antigen test disagree with the clinical impression, a treponemal antigen test such as the FTA-ABS should be performed. Dr.T.V.Rao MD 39
  • 40. Non-syphilitic Conditions Giving Biologic False-Positive Results • Viral pneumonia • Lupus erythematous • Measles • pregnancy • drug abuse • • • • Malaria Leprosy Relapsing fever Infectious Mononucleosis • Atypical pneumonia Dr.T.V.Rao MD 40
  • 41. Resolving False Positive RPR Tests • False positive RPR tests may be resolved by testing the patient’s serum with a specific treponemal antigen tests. Dr.T.V.Rao MD 41
  • 42. Treponema-Specific Tests for Syphilis Dr.T.V.Rao MD 42
  • 43. Confirmatory Tests for Syphilis • Treponemal tests are used to confirm reactive non –treponemal procedures. TPHA testing is now routinely done • A positive FTA-ABS test almost always remains positive and therefore is not recommended for monitoring therapy. Dr.T.V.Rao MD 43
  • 44. TREPONEMAL TESTS FTA-ABS • Used as a confirmatory tests. • Sensitivity and specificity high. – 85% of patients with primary syphilis are reactive – 99% with secondary syphilis – > 95% with late syphilis (It may be the only test with a positive result for patients with cardiovascular or neurologic syphilis). • Remains reactive for life in most, despite adequate therapy. Only 15-25 % of those treated for primary syphilis may turn negative by 23 yrs. • False positive in other treponemal diseases (pinta, yaws..) and other spirochete diseases (Lyme, leptospirosis…) MHA-TP test (microhemagglutination assay for T. pallidum; agglutination of RBCs to which T. pallidum antigens have been fixed is the basis). Dr.T.V.Rao MD 44
  • 45. TPHA and FTA-ABS Testing are commonly used Confirmatory Tests Dr.T.V.Rao MD 45
  • 46. For Routine Testing a Combination of VDRL or RPR and TPHA is highly preferred • TPHA Test is a sensitive passive haemagglutination test, that detects specific Treponema pallidum antibodies in serum within one hour. Used in combination, the VDRL or RPR and TPHA Tests provide accurate and reliable confirmation of active syphilis infection. No specialized equipment is required and results are clearly visible and easily interpreted. Dr.T.V.Rao MD 46
  • 47. Microhemagglutination assay • The MHA-TP and TPHA are used to confirm a syphilis infection after another method tests positive for the syphilis bacteria. The MHA-TP and TPHA tests detect antibodies to the bacteria that cause syphilis and can be used to detect syphilis in all stages, except during the first 3 to 4 weeks when antibody levels are too low. These tests are also suitable for use as a screening procedure. Neither of these tests is suitable for use on cerebrospinal fluid (CSF). Dr.T.V.Rao MD 47
  • 48. Principles of TPHA Test • TPHA (Treponema Pallidum Hemagglutination) is an indirect hemagglutination assay carried out on micro plates for the qualitative and semiqualitative detection of anti- Treponema pallidum specific antibodies in human serum. Avian blood cells stabilized and sensitized with a solution of T. pallidum antigen agglutinate in the presence of anti-T Pallidum antibodies, exhibiting a typical agglutination pattern. Dr.T.V.Rao MD 48
  • 49. Reading TPHA Results • The upper, left-hand well contains a positive control test. The red cells have had treponemal antigens attached and antibodies in the serum have caused these cells to agglutinate and form a mat across the bottom of the well. These antibodies can be presumed to be specific for Treponemes, since otherwise identical red cells that have not had the treponemal antigens attached do not cause haemagglutination, as seen in the bottom, left-hand well. A negative serum test is shown in the center and a patient's test is on the right. This result supports a diagnosis of Dr.T.V.Rao MD syphilis. 49
  • 50. EIA tests for Syphilis • Enzyme immunoassay (EIA), also known as an enzyme linked immunosorbent assay (ELISA), for syphilis is a relatively new invention first appearing on the market in the mid-1990s. There are numerous benefits to the EIA platform over earlier technologies. Firstly, the majority of diseases that are considered to be of clinical and public health importance already exist in an EIA format, which is highly standardized even across international boundaries. This familiarity allows new EIAs to be readily accepted by clinicians and technicians with minimal difficulty. It also limits the need to purchase new capital equipment since most labs will already be equipped to handle EIAs. Dr.T.V.Rao MD 50
  • 51. EIA tests Syphilis Gaining Importance • There have been several developments in particularly the advent of enzyme immunoassays (EIAs) and, lately, the commercial availability of recombinant antigenbased tests Dr.T.V.Rao MD 51
  • 52. Fluorescent Treponemal Antibody Absorption (FTA-abs) • The FTA-abs test detects antibodies to T. pallidum and can be used to detect syphilis infection at any stage except during the first 3 to 4 weeks after exposure (which is about the same time frame that the VDRL/RPR tests become effective) and in tertiary stages of the disease. In the secondary stage of syphilis, the FTA-abs test is most reliable and is reportedly positive in 100 percent of cases. It can be adapted to detect either IgG or IgM antibody. Dr.T.V.Rao MD 52
  • 53. Gold Standard Confirmatory test • The FTA-abs is still generally regarded as the ‘gold standard’, but it has a number of limitations. It is a subjective test and difficult to standardize. It is sensitive, but the TPHA is more sensitive, except in the third and fourth weeks of infection; the TPHA is also more specific2. Dr.T.V.Rao MD 53
  • 54. Sensitivity of Serological Tests in Untreated Syphilis Stage of Disease (Percent Positive [Range]) Test Primary Secondary Latent Tertiary VDRL 78 (74-87) 100 95 (88-100) 71 (37-94) RPR 86 (77-99) 100 98 (95-100) 73 FTA-ABS* 84 (70-100) 100 100 96 Treponemal Agglutination* 76 (69-90) 100 97 (97-100) 94 93 100 100 EIA *FTA-ABS and TP-PA are generally considered equally sensitive in the primary stage of disease. Dr.T.V.Rao MD 54
  • 55. Diagnosis Causes of False-Positive Reactions in Serologic Tests for Syphilis Disease RPR/VDRL Age Autoimmune Diseases FTA-ABS TP-PA Yes Yes Cardiovascular Disease Yes Yes Yes -- Dermatologic Diseases Yes Yes Drug Abuse Yes Yes Febrile Illness Yes Glucosamine/chondroitin sulfate Leprosy Possibly Yes Lyme disease No -- Yes Malaria Yes No Pinta, Yaws Yes Yes Yes Pregnancy Yes* Recent Immunizations Yes -- -- STD other than Syphilis Yes *May cause increase in titer in women previously successfully treated for syphilis Dr.T.V.Rao MD Source: Syphilis Reference Guide, CDC/National Center for Infectious Diseases, 2002 55
  • 56. AIDS and Syphilis • The Serological Tests in AIDS and HIV related infections should be interpreted with caution and expertise, need a better understanding of the progress of the Disease. Dr.T.V.Rao MD 56
  • 57. Gonorrhea Dr.T.V.Rao MD 57
  • 58. Drips Gonorrhea - Clinical Manifestations • Urethritis - male – – – – Incubation: 1-14 d (usually 2-5 d) Sx: Dysuria and urethral discharge (5% asymptomatic) Dx: Gram stain urethral smear (+) > 98% culture Complications • Urogenital infection - female – – – – Endocervical canal primary site 70-90% also colonize urethra Incubation: unclear; sx usually in l0 d Sx: majority asymptomatic; may have vaginal discharge, dysuria, urination, labial pain/swelling, abd. pain – Dx: Gram stain smear (+) 50-70% culture – Complications Dr.T.V.Rao MD 58
  • 59. Drips Gonorrhea Dr.T.V.Rao MD Source: Florida STD/HIV Prevention Training Center 59
  • 60. Drips Gonorrhea Gram Stain Dr.T.V.Rao MD Source: Cincinnati STD/HIV Prevention Training Center 60
  • 61. Diagnosis not Easy • Three levels of diagnosis are defined on the basis of clinical findings or the results of laboratory diagnostic tests. A definitive diagnosis of gonorrhea must be obtained for medico legal purposes. Dr.T.V.Rao MD 61
  • 62. Suggestive diagnosis • Suggestive diagnosis is defined by the presence of: • A mucopurulent endocervical or urethral exudate on physical examination and sexual exposure to a person infected with N. gonorrhoea. Dr.T.V.Rao MD 62
  • 63. Presumptive diagnosis of gonorrhoea is made on the basis of one of the following three criteria: • Typical gram-negative intracellular diplococci on microscopic examination of a smear of urethral exudate from men or endocervical secretions from women*; • Growth of a gram-negative, oxidase-positive diplococcus, from the urethra (men) or endocervix (women), on a selective culture medium, and demonstration of typical colonial morphology, positive oxidase reaction, and typical gram- negative morphology; Dr.T.V.Rao MD 63
  • 64. Observation Under Microscope • The observation of gramnegative, intracellular diplococci on microscopic examination of endocervical secretions from women must be supported by a positive result from a test from either 2 or 3 to make a laboratory diagnosis of “presumptive N. gonorrhoeae.” Dr.T.V.Rao MD 64
  • 65. Definitive diagnosis of gonorrhea requires: • Isolation of N. gonorrhoeae from sites of exposure (e.g., urethra, endocervix, throat, rectum) by culture (usually a selective medium) and demonstrating typical colonial morphology, positive oxidase reaction, and typical gram-negative morphology and confirmation of isolates by biochemical, enzymatic, serologic, or nucleic acid testing e.g., carbohydrate utilization, rapid enzyme substrate tests, serologic methods such as coagglutination or fluorescent antibody tests supplemented with additional tests that will ensure accurate identification of isolates, or a DNA probe culture confirmation technique. Dr.T.V.Rao MD 65
  • 66. Newer Methods in Diagnosis of Gonorrhea • Detection of N. gonorrhoeae by a nonculture laboratory test (Antigen detection test (e.g., Gonozyme [Abbott]), direct specimen nucleic acid probe test (e.g., Pace II [GenProbe]), nucleic acid amplification test (e.g., LCR [Abbott]). Dr.T.V.Rao MD 66
  • 67. Definitive diagnosis of gonorrhea requires: • Isolation of N. gonorrhoeae from sites of exposure (e.g., urethra, endocervix, throat, rectum) by culture (usually a selective medium) and demonstrating typical colonial morphology, positive oxidase reaction, and typical gram-negative morphology Dr.T.V.Rao MD 67
  • 68. Definitive diagnosis of gonorrhea requires: • Confirmation of isolates by biochemical, enzymatic, serologic, or nucleic acid testing e.g., carbohydrate utilization, rapid enzyme substrate tests, serologic methods such as coagglutination or fluorescent antibody tests supplemented with additional tests that will ensure accurate identification of isolates, or a DNA probe culture confirmation technique. Dr.T.V.Rao MD 68
  • 69. Drips Nongonococcal Urethritis • Etiology: – 20-40% C. trachomatis – 20-30% genital mycoplasmas (Ureaplasma urealyticum, Mycoplasma genitalium) – Occasional Trichomonas vaginalis, HSV – Unknown in ~50% cases • Sx: Mild dysuria, mucoid discharge • Dx: Urethral smear 5 PMNs (usually 15)/OI field Urine microscopic 10 PMNs/HPF Leukocyte esterase (+) 69 Dr.T.V.Rao MD
  • 70. Chlamydial Infections Dr.T.V.Rao MD 70
  • 71. Drips Chlamydial Infections • More than three million new cases annually • Responsible for causing cervicitis, urethritis, Proctitis, lymphogranuloma venereum, and pelvic inflammatory disease • Direct and indirect cost of chlamydial infections run into billions of dollars • Potential to transmit to newborn during delivery – Conjunctivitis, pneumonia Dr.T.V.Rao MD 71
  • 72. What are the symptoms of chlamydia? • Chlamydia is known as a ‘silent’ infection because most infected people have no symptoms. If symptoms do occur, they may not appear until several weeks after exposure. Even when it causes no symptoms, chlamydia can damage a woman’s reproductive organs. Dr.T.V.Rao MD 72
  • 73. Drips Laboratory Tests for Chlamydia • Tissue culture has been the standard – Specificity approaching 100% – Sensitivity ranges from 60% to 90% • Non-amplified tests – Enzyme Immunoassay (EIA), e.g. Chlamydiazyme • sensitivity and specificity of 85% and 97% respectively • useful for high volume screening • false positives – Nucleic Acid Hybridization (NA Probe), e.g. Gen-Probe Pace2 • sensitivities ranging from 75% to 100%; specificities greater than 95% • detects chlamydial ribosomal RNA • able to detect gonorrhea and chlamydia from one swab • need for large amounts of sample DNA Dr.T.V.Rao MD 73
  • 74. Drips Laboratory Tests for Chlamydia (continued) • DNA amplification assays – polymerase chain reaction (PCR) – ligase chain reaction (LCR) • Sensitivities with PCR and LCR 95% and 85-98% respectively; specificity approaches 100% • LCR ability to detect chlamydia in first void urine Dr.T.V.Rao MD 74
  • 75. Drips Pelvic Inflammatory Disease (PID) • l0%-20% women with GC develop PID • In Europe and North America, higher proportion of C. trachomatis than N. gonorrhoeae in women with symptoms of PID • CDC minimal criteria – uterine adnexal tenderness, cervical motion tenderness • Other symptoms include – endocervical discharge, fever, lower abdominal pain • Complications: – Infertility: 15%-24% with 1 episode PID secondary to GC or chlamydia – 7X risk of ectopic pregnancy with 1 episode PID – chronic pelvic pain in 18% Dr.T.V.Rao MD 75
  • 76. Chlamydia serology • Chlamydia serology (complement fixation titers >1:64) can support the diagnosis of LGV in the appropriate clinical context. Comparative data between types of serologic tests are lacking, and the diagnostic utility of serologic methods other than complement fixation and some micro immunofluorescence procedures has not been established. Dr.T.V.Rao MD 76
  • 77. Chancroid • The combination of a painful genital ulcer and tender Suppurative inguinal adenopathy suggests the diagnosis of Chancroid A probable diagnosis of Chancroid, for both clinical and surveillance purposes, can be made if all of the following criteria are met: 1) the patient has one or more painful genital ulcers; 2) the patient has no evidence of T. pallidum infection by dark field examination of ulcer exudate or by a serologic test for syphilis performed at least 7 days after onset of ulcers; Dr.T.V.Rao MD 77
  • 78. Chancroid • 3) the clinical presentation, appearance of genital ulcers and, if present, regional lymphadenopathy are typical for Chancroid; and 4) a test for HSV performed on the ulcer exudate is negative. Dr.T.V.Rao MD 78
  • 79. Chancroid • A definitive diagnosis of Chancroid requires the identification of H. ducreyi on special culture media that is not widely available from commercial sources; even when these media are used, sensitivity is <80% (145). Dr.T.V.Rao MD 79
  • 80. Granuloma Inguinale (Donovanosis) • Granuloma inguinale is a genital ulcerative disease caused by the intracellular gramnegative bacterium Klebsiella granulomatis (formerly known as Calymmatobacterium granulomatis). The disease occurs rarely in the United States, although it is endemic in some tropical and developing areas, including India; Papua, New Guinea; the Caribbean; central Australia; and southern Africa (192,193). Dr.T.V.Rao MD 80
  • 81. Granuloma Inguinale • Clinically, the disease is commonly characterized as painless, slowly progressive ulcerative lesions on the genitals or perineum without regional lymphadenopathy; subcutaneous granulomas (pseudoboboes) might also occur. The lesions are highly vascular (i.e., beefy red appearance) and bleed easily on contact. Dr.T.V.Rao MD 81
  • 82. Granuloma Inguinale • The causative organism is difficult to culture, and diagnosis requires visualization of darkstaining Donovan bodies on tissue crush preparation or biopsy. No FDA-cleared molecular tests for the detection of K. granulomatis DNA exist, but such an assay might be useful when undertaken by laboratories that have conducted a CLIA verification study. Dr.T.V.Rao MD 82
  • 83. Lymph granuloma Venereum • Lymph granuloma venereum (LGV) is caused by C. trachomatis serovars L1, L2, or L3 . The most common clinical manifestation of LGV among heterosexuals is tender inguinal and/or femoral lymphadenopathy that is typically unilateral. Dr.T.V.Rao MD 83
  • 84. Lymph granuloma Venereum • Diagnosis is based on clinical suspicion, epidemiologic information, and the exclusion of other etiologies for proctocolitis, inguinal lymphadenopathy, or genital or rectal ulcers. C. trachomatis testing also should be conducted, if available. Dr.T.V.Rao MD 84
  • 85. Lymph granuloma Venereum • Genital and lymph node specimens (i.e., lesion swab or bubo aspirate) can be tested for C. trachomatis by culture, direct immunofluorescence, or nucleic acid detection. NAATs for C. trachomatis are not FDA-cleared for testing rectal specimens, although some laboratories have performed the CLIA validation studies that are needed to provide results for clinical management. Additional molecular procedures (e.g., PCR-based genotyping) can be used to differentiate LGV from non-LGV C. trachomatis, but these are not widely available. Dr.T.V.Rao MD 85
  • 86. • • • • Trichomoniasis An estimated 5 million new cases occur each year in women and men. Occurs in vagina of women so may be sexually transmitted to men using infected washcloths and towels. It is transmitted to the baby during delivery. It also can occur in the urethra (carries urine to penis) in men, doesn’t have symptoms usually. SYMPTOMS: Appear within 5 to 28 days of exposure Women usually have a vaginal discharge that FEMALE SYMPTOMS: Itching and burning at the outside of the opening of the vagina and vulva. Painful and frequent urination Heavy, unpleasant smelling greenish, yellow discharge MALE SYMPTOMS: Usually nothing, or discomfort in urethra, inflamed head of the penis. Dr.T.V.Rao MD 86
  • 87. Candidiasis – Yeast Fungus  Yeast fungus that may or may not be transmitted by sexual intercourse.  Caused by high doses of antibiotics. It is usually caused by altering the Ph of the vagina. SYMPTOMS: A thick cheesy vaginal discharge Severe itching Dr.T.V.Rao MD 87
  • 88. Background Bacterial Vaginitis • Controversy: STD - yes or no • Need for treatment – 1980: only if patient complains – 2002: increased risk of: • • • • • • • • Preterm birth / premature rupture of membranes Amniotic fluid infection Chorioamnionitis / Postpartum endometritis Pelvic inflammatory disease Postsurgical infection Cervical intraepithelial neoplasia Mucopurulent cervicitis Acquisition of HIV infection Dr.T.V.Rao MD 88
  • 89. HPV and Cervical Cancer • Infection is generally indicated by the detection of HPV DNA • HPV infection is causally associated with cervical cancer and probably other anogenital squamous cell cancers (e.g. anal, penile, vulvar, vaginal) • Over 99% of cervical cancers have HPV DNA detected within the tumor • Routine Pap smear screening ensures early detection (and treatment) of pre-cancerous lesions 89 Dr.T.V.Rao MD
  • 90. Definitive diagnosis of HPV • A definitive diagnosis of HPV infection is based on detection of viral nucleic acid (i.e., DNA or RNA) or capsid protein. Tests that detect several types of HPV DNA in cells scraped from the cervix are available and might be useful in the triage of women with atypical squamous cells of undetermined significance (ASC-US) or in screening women aged ≥30 years in conjunction with the Pap test Dr.T.V.Rao MD 90
  • 91. Testing for HPV Infection • This HPV test can identify 13 of the highrisk types of HPV that are associated with the development of cervical cancer. The results of HPV DNA testing can help healthcare providers decide if further tests or treatments are Dr.T.V.Rao MD necessary. 91
  • 92. Non-Curable STDs HIV (Human Immunodeficiency Virus) • HIV is the virus that causes AIDS. You can get HIV if you do any of the following: – Have sex with someone who has HIV. It can be spread by having vaginal, anal, or oral sex. Your partner could have HIV and not know it. – Share needles with someone who has HIV. Dr.T.V.Rao MD 92
  • 93. Sexually Transmitted Infections can be Reduced with Sex Education Dr.T.V.Rao MD 93
  • 94. For more articles of Interest on Infectious Diseases visit…. Dr.T.V.Rao MD 94
  • 95. • Programme Created by Dr.T.V.Rao MD for Medical , Paramedical and Everyone • Email • doctortvrao@gmail.com Dr.T.V.Rao MD 95