Topics included :- What are protozoans; list of diseases caused by them (Malaria, amoebiasis, leishmaniasis, trypanosomiasis, balantidiasis, giardiasis, trichomoniasis, toxoplasmosis, pneumocytosis); drugs in treating protozoan diseases

1. PROTOZOAN DISEASES
IN
HUMAN BEINGS
BY : S. DASH

2. WHAT ARE PROTOZOANS ??
• PROTOZOA (ALSO PROTOZOAN,
PLURAL PROTOZOANS) IS AN
INFORMAL TERM FOR SINGLE-
CELLED EUKARYOTES, EITHER
FREE-LIVING OR PARASITIC,
WHICH FEED ON ORGANIC MATTER
SUCH AS OTHER
MICROORGANISMS OR ORGANIC
TISSUES AND DEBRIS.

3. LIST OF DISEASES CAUSED BY PROTOZOANS:
1. MALARIA
2. AMOEBIASIS
3. LEISHMANIASIS
4. TRYPANOSOMIASIS (AKAAFRICAN SLEEPING DISEASE)
5. BALANTIDIASIS
6. GIARDIASIS
7. TRICHOMONIASIS
8. TOXOPLASMOSIS
9. PNEUMOCYTOSIS

4. MALARIA
• Four species of plasmodium protozoa that causes malaria in humans.
• Most common of them are P.falciparum and P.vivax.
• Symptoms occur in between 10-16 days after infection by mosquitos.
• Paroxysms frequently begin with bed-shaking chills followed by high-
fevers, sweating , headache and muscular pain.
• Spleen becomes enlarged and tender, anaemia eventually develops.

5. Diagnosis
• Various test kits are available to detect antigens derived from malaria
parasites, these are called rapid diagnostic tests offer a useful alterenative
to microscopy.
Control
• Elimination of the insect vector which transmits the disease.

6. .

7. .

8. AMOEBIASIS
• Caused by Entamoeba histolytica.
• Transmitted from person to person in infected food and water , by flies and by direct contact.
• Clinical indications like abdominal discomfort, with slight diarrhoea alternating with constipation to severe
diarrhoea with blood and mucus in the stools.
• Abscesses may be formed in the liver or the lungs or even sometimes in the brain.
• Diagnosis-microscopic examination of stool samples, sigmoidoscopy, blood test.
• Treatment-Iodoquinol , metronidazole etc.

9. AMOEBIASIS

10. LEISHMANIASIS
• Clinical forms of leishmaniasis are caused by infection with three different species: L.Donovani in visceral
leishmaniasis, commonly called kala azar ; L.Tropica in oriental sore called cutaneous leishmaniasis and
mucocutaneous leishmaniasis and L.Basiliensis in the disease called espundia.
• Transmitted to humans by bites of sandflies.
• Symptoms include-irregular and recurrent fever, leukopenia, enlargement of spleen and liver. Lesions and
ulcers develop. The lesions result in extensive scarring and mutilation.
• Diagnosis-finding of leishman-donovan bodies in stained smears from lesions or infected organs.
• Treatment-liposomal amphotericin B, miltefosin and sodium stibogluconate.

11. TRYPANOSOMIASIS (AKAAFRICAN SLEEPING DISEASE)
• Infectious agent-Trypanosoma brucei gambiense or Trypanosoma brucei rhodesiense.
• The tse-tse fly bite erupts into a red chancre sore, symptoms of first stage include-fever, swollen lymph
glands, blood in urine, aching muscles and joints, headaches and irritability. [FIRST STAGE]
• In the second stage symptoms include-changes in personality, alteration of biological clock, confusion,
slurred speech, seizures and difficulty in walking and talking.
• Diagnosis-recognition of flagellate on a blood smear, motile organisms may be visible in a buffy coat when
blood sample is spun down.
• Treatment- stage-1:pentamidine or suramin (intramuscular or intravenous)
Stage-2: melarsoprol or eflornithine(intravenously)

12. TRYPANOSOMIASIS

13. BALANTIDIASIS
• A large intestine infection with Balantidium coli, which is a ciliated protozoan. Passes
directly to humans by contact with pig faeces and indirectly by drinking contaminated
water.
• It resides in the lumen of the intestine and obtains food by the ingestion of bacteria.
• Symptoms include-fever, vomiting, abdominal pain, dehydration and bloody diarrhoea.
• Diagnosis-stool testing(searching for trophozoites)
• Treatment-tetracycline, iodoquinol etc.

14. GIARDIASIS
• Infectious agent-Giardia lambia.
• Infection of small intestine, manifested by diarrhoea and abdominal cramps.
• Transmitted by contaminated food and water, pet dogs and cats also contract giardia.
• Clinical signs include weight loss, anaemia and even poor protein absorption.
• Diagnosis-stool test, enteroscopy
• Treatment-metronidazole, tinidazole etc.

15. TRICHOMONIASIS
• Caused by one-celled protozoan organism- Trichomonas vaginalis. Organism mainly found in
vaginal secretions and infects both men and women.
• The organisms reproduce within the vagina or the urethra by longitudinal binary fission.
• Sexually transmitted disease is a type of vaginitis.
• Infection in males is usually asymptomatic except in cases seminal vesicles and prostrate.
• In women, a thin watery vaginal discharge is the most prominent symptom, usually accompanied
by itching and burning.
• Diagnosed by-cell cultures, antigen test, tests that look for Trichomonas DNA.
• Treatment-metronidazole or tinidazole.

16. TRICHOMONIASIS

17. TOXOPLASMOSIS
• Infectious agent : Toxoplasma gondii ,found in cat faeces and undercooked meat, especially
venison, lamb and pork.
• Can be deadly or cause serious birth defects for a foetus if the mother is infected.
• Symptoms include a fever, swollen lymph nodes, a headache, muscle ache and sore throat.
• Diagnosis-Presence of antibodies
• Treatment-If severe, pyrimethamine and sulfadiazine is prescribed.

18. TOXOPLASMOSIS

19. PNEUMOCYSTIS
• Infectious agent: Pneumocystis carinii
• Transmitted by formites or respiratory droplets.
• Usually seen in people with weak immune system.
• Symptoms include-fever, shortness of breath, weight loss, night sweats.
• Pneumothorax is a well known complication of Pneumocystis.
• The diagnosis can be confirmed by chest X-ray and an arterial oxygen level, Gallium-67 scans are also useful.
• Most commonly used medication is trimethoprim.

20. DRUGS IN TREATING PROTOZOAN DISEASES:
SR.
NO.
DISEASE DRUGS
1. LEISHMANIASIS SODIUM STIBOGLUCONATE
2. TRYPANOSOMIASIS(early) PENTAMIDE ISETHIONATE SURAMIN
3. AMOEBIASIS METRONIDAZOLE + IODOQUINOL
4. FALCIPARUM MALARIA CHLOROQUINONE PHOSPHATE + PRIMAQUINE
PHOSPHATE
5. CHLORQUINE RESISTANT MALARIA QUININE SULFATE+PYRIMETHAMINE + SULFADIAZINE

21. REFERENCES
• Microbiology by Michael.J.Pelczar, Jr.E.C.S. Chan, Noel.R. Kreig
• Textbook of microbiology by Ananthanarayan and Paniker
• Microbiology by Presscott.
• http://en.wikipedia.org/wiki/

22. THANK YOU !!!!!!