1. Parasitology Sporozoons

2. Parasitology/Sporozoons (3 hours) 1.Defines “Sporozoon’’ 1.1 Lists the sporozoon classification. 1.2. Defines the cell structure of sporozoons. 1.3. Defines the life cyles of sporozoons; lists the cysts, trophozoits, oocysts, promastigot, amastigot structures. 2.Lists the clinical tables related with sporozoons and defines pathogenetic mechanisms. 2.1. Defines the clinical importance of sporozoons. 2.2. Defines the sample taking related with infections of sporozoons. 2.3. Lists the laboratory diagnostic methods.

3. Flagellates Intestinal flagellates Giardia intestinalis Giardia intestinalis Trichomonas spp Trichomonas spp Dientamoeba fragilis Dientamoeba fragilis Trichomonas vaginalis Trichomonas vaginalis Hemoflagellates Leishmania donovani Trypanosoma cruzi

4. Giardia intestinalis (lamblia) Cysts are resistant forms and are responsible for transmission of giardiasis. Cysts are resistant forms and are responsible for transmission of giardiasis. Both cysts and trophozoites can be found in the feces (diagnostic stages) Both cysts and trophozoites can be found in the feces (diagnostic stages) The cysts are hardy and can survive several months in cold water. The cysts are hardy and can survive several months in cold water. Infection occurs by the ingestion of cysts in contaminated water, food, or by the fecal-oral route (hands or fomites) Infection occurs by the ingestion of cysts in contaminated water, food, or by the fecal-oral route (hands or fomites) Because the cysts are infectious when passed in the stool or shortly afterward, person-to-person transmission is possible Because the cysts are infectious when passed in the stool or shortly afterward, person-to-person transmission is possible

6. Symptoms diarrhea, diarrhea, abdominal pain, abdominal pain, bloating, bloating, nausea, nausea, vomiting. vomiting. incubation period: 1 to 14 days (average of 7 days)

7. Diagnosis cysts or trophozoites in the feces, using direct mounts cysts or trophozoites in the feces, using direct mounts (repeated samplings) samples of duodenal fluid (e.g., Enterotest) samples of duodenal fluid (e.g., Enterotest) duodenal biopsy may demonstrate trophozoites duodenal biopsy may demonstrate trophozoites alternate methods alternate methods antigen detection tests enzyme immunoassays, antigen detection tests enzyme immunoassays, detection of parasites by immunofluorescence. detection of parasites by immunofluorescence.

10. Trichomonas vaginalis resides in the female lower genital tract and the male urethra and prostate resides in the female lower genital tract and the male urethra and prostate transmitted among humans, its only known host, primarily by sexual intercourse transmitted among humans, its only known host, primarily by sexual intercourse no cyst formation no cyst formation

12. Symptoms vaginitis with a purulent discharge is the prominent symptom, vaginitis with a purulent discharge is the prominent symptom, vulvar and cervical lesions, vulvar and cervical lesions, abdominal pain, abdominal pain, dysuria dysuria dyspareunia. dyspareunia. In men asymptomatic; asymptomatic; urethritis, urethritis, epididymitis, epididymitis, prostatitis prostatitis the incubation period is 5 to 28 days. the incubation period is 5 to 28 days.

13. Diagnosis microscopic examination of wet mounts microscopic examination of wet mounts culture culture

14. Dientomoeba fragilis not an ameba but a flagellate not an ameba but a flagellate no cyst formation no cyst formation

16. Symptoms diarrhea, diarrhea, abdominal pain, abdominal pain, anorexia, anorexia, nausea, nausea, vomiting, vomiting, fatigue, fatigue, weight loss. weight loss.

17. Diagnosis detection of trophozoites in permanently stained fecal smears (e.g., trichrome). detection of trophozoites in permanently stained fecal smears (e.g., trichrome). not detectable by stool concentration methods. not detectable by stool concentration methods. trophozoites can be easily overlooked,they are pale-staining and their nuclei may resemble those of Endolimax nana or Entamoeba hartmanni. trophozoites can be easily overlooked,they are pale-staining and their nuclei may resemble those of Endolimax nana or Entamoeba hartmanni.

20. Leishmania donovani a vector-borne disease a vector-borne disease transmitted by sandflies transmitted by sandflies caused by obligate intracellular protozoa of the genus Leishmania caused by obligate intracellular protozoa of the genus Leishmania

22. Promastigotes Promastigotes amastigotes amastigotes in the sandfly's midgut, the parasites differentiate into promastigotes in the sandfly's midgut, the parasites differentiate into promastigotes in Mexico Central America, South America southern Europe Asia (not Southeast Asia), the Middle East, and Africa and Africa

23. Symptoms Cutaneous leishmaniasis (L.tropica) one or more sores on their skin. one or more sores on their skin. the sores can change in size and appearance over time. the sores can change in size and appearance over time. they often end up looking somewhat like a volcano, with a raised edge and central crater. they often end up looking somewhat like a volcano, with a raised edge and central crater. a scab covers some sores. a scab covers some sores. the sores can be painless or painful. the sores can be painless or painful. some people have swollen glands near the sores (for example, in the armpit if the sores are on the arm or hand). some people have swollen glands near the sores (for example, in the armpit if the sores are on the arm or hand).

24. Symptoms Visceral leishmaniasis (kala-azar)(L.donovani) fever, fever, weight loss, weight loss, enlarged spleen and liver (usually the spleen is bigger than the liver). enlarged spleen and liver (usually the spleen is bigger than the liver). Some patients have swollen glands. Some patients have swollen glands. Certain blood tests are abnormal. low blood counts, including a low red blood cell count (anemia), low white blood cell count, and low platelet count. Certain blood tests are abnormal. low blood counts, including a low red blood cell count (anemia), low white blood cell count, and low platelet count. Some patients develop post kala-azar dermal leishmaniasis. Some patients develop post kala-azar dermal leishmaniasis. Visceral leishmaniasis is becoming an important opportunistic infection in areas where it coexists with HIV. Visceral leishmaniasis is becoming an important opportunistic infection in areas where it coexists with HIV.

25. Diagnosis Giemsa-stained slides Giemsa-stained slides culture (using for example the diphasic NNN medium) culture (using for example the diphasic NNN medium) Antibody detection Antibody detection

27. Trypanosoma cruzi Chagas disease, Chagas disease, a zoonotic disease a zoonotic disease transmitted to humans transmitted to humans by blood-sucking triatomine bugs (kissing bug) by blood-sucking triatomine bugs (kissing bug) Chronic Chagas disease is a major health problem in many Latin American countries Chronic Chagas disease is a major health problem in many Latin American countries

29. trypomastigotes trypomastigotes amastigotes amastigotes trypomastigotes trypomastigotes amastigotes amastigotes Trypanosoma cruzi can also be transmitted through blood transfusions, organ transplantation, transplacentally, in laboratory accidents.

30. Symptoms fever, fever, anorexia, anorexia, lymphadenopathy, lymphadenopathy, mild hepatosplenomegaly, mild hepatosplenomegaly, myocarditis. myocarditis. Chronic stage may not occur for years or even decades after initial infection. cardiomyopathy (the most serious manifestation); cardiomyopathy (the most serious manifestation); megaesophagus megaesophagus megacolon; megacolon; weight loss. weight loss. Chronic Chagas disease and its complications can be fatal.

31. Diagnosis Microscopic examination: of fresh anticoagulated blood, or its buffy coat, for motile parasites; of fresh anticoagulated blood, or its buffy coat, for motile parasites; of thin and thick blood smears stained with Giemsa, for visualization of of thin and thick blood smears stained with Giemsa, for visualization ofparasites. Isolation of the agent by: inoculation into mice; inoculation into mice; culture in specialized media (e.g. NNN, LIT); culture in specialized media (e.g. NNN, LIT); xenodiagnosis, where uninfected reduviid bugs are fed on the patient's blood, and their gut contents examined for parasites 4 weeks later. xenodiagnosis, where uninfected reduviid bugs are fed on the patient's blood, and their gut contents examined for parasites 4 weeks later.

34. Treatment benznidazole or nifurtimox benznidazole or nifurtimox In the chronic stage, e.g., pacemaker for heart block In the chronic stage, e.g., pacemaker for heart block

35. Trypanosoma brucei T. b. gambiense -West African sleeping sickness T. b. gambiense -West African sleeping sickness T. b. rhodesiense - East African sleeping sickness. T. b. rhodesiense - East African sleeping sickness. T. b. brucei - under normal conditions does not infect humans T. b. brucei - under normal conditions does not infect humans tsetse fly (genus Glossina) tsetse fly (genus Glossina)

37. Symptoms a trypanosomal chancre can develop on the site of inoculation. a trypanosomal chancre can develop on the site of inoculation. a hemolymphatic stage (fever, lymphadenopathy, and pruritus.) a hemolymphatic stage (fever, lymphadenopathy, and pruritus.) the meningoencephalitic stage ( headaches, somnolence, abnormal behavior, loss of consciousness and coma) the meningoencephalitic stage ( headaches, somnolence, abnormal behavior, loss of consciousness and coma) the course of infection is much more acute with T. b. rhodesiense than T. b. gambiense. the course of infection is much more acute with T. b. rhodesiense than T. b. gambiense.

38. Diagnosis microscopic examination of chancre fluid, lymph node aspirates, blood, bone marrow, or, in the late stages of infection, cerebrospinal fluid. microscopic examination of chancre fluid, lymph node aspirates, blood, bone marrow, or, in the late stages of infection, cerebrospinal fluid. a wet preparation should be examined for the motile trypanosomes, and in addition a smear should be fixed, stained with Giemsa (or Field), and examined. a wet preparation should be examined for the motile trypanosomes, and in addition a smear should be fixed, stained with Giemsa (or Field), and examined. the Card Agglutination Trypanosomiasis Test (CATT) test is of value for epidemiologic surveys or screening of T. b. gambiense the Card Agglutination Trypanosomiasis Test (CATT) test is of value for epidemiologic surveys or screening of T. b. gambiense

40. Amebas Intestinal amebas Entamoeba histolytica Entamoeba histolytica Entamoeba coli Entamoeba coli Balantidium coli Balantidium coli Free-living amebas Naegleria fowleri Acanthamoeba castellani

41. Amebiasis Entemoeba histolytica Entemoeba histolytica Entemoeba coli Entemoeba coli Entemoeba hartmanni Entemoeba hartmanni

43. Symptoms asymptomatic infection ("luminal amebiasis"), asymptomatic infection ("luminal amebiasis"), invasive intestinal amebiasis invasive intestinal amebiasis dysentery, dysentery, colitis, colitis, appendicitis, appendicitis, toxic megacolon, toxic megacolon, amebomas, amebomas, invasive extraintestinal amebiasis invasive extraintestinal amebiasis liver abscess, liver abscess, peritonitis, peritonitis, pleuropulmonary abscess, pleuropulmonary abscess, cutaneous genital amebic lesions cutaneous genital amebic lesions

44. Diagnosis Fresh stool: wet mounts and permanently stained preparations (e.g., trichrome). Fresh stool: wet mounts and permanently stained preparations (e.g., trichrome). Concentrates from fresh stool: wet mounts, with or without iodine stain, and permanently stained preparations (e.g., trichrome). Concentration procedures, however, are not useful for demonstrating trophozoites. Concentrates from fresh stool: wet mounts, with or without iodine stain, and permanently stained preparations (e.g., trichrome). Concentration procedures, however, are not useful for demonstrating trophozoites. E. histolytica trophozoites can also be identified in aspirates or biopsy samples obtained during colonoscopy or surgery E. histolytica trophozoites can also be identified in aspirates or biopsy samples obtained during colonoscopy or surgery Erythrophagocytosis is the only morphologic characteristic that can be used to differentiate E. histolytica from the nonpathogenic E. dispar Erythrophagocytosis is the only morphologic characteristic that can be used to differentiate E. histolytica from the nonpathogenic E. dispar

45. E.histolytica trophozoites

46. E.histolytica cysts

47. E.coli trophozoites

48. E.coli cysts

49. E.hartmanni

50. Balantidum coli a large ciliated protozoan parasite a large ciliated protozoan parasite Most cases are asymptomatic. Most cases are asymptomatic. Clinical manifestations Clinical manifestations persistent diarrhea, persistent diarrhea, occasionally dysentery, occasionally dysentery, abdominal pain, abdominal pain, weight loss. weight loss.

52. Diagnosis trophozoites in stool specimens or in tissue collected during endoscopy. Cysts are less frequently encountered. trophozoites in stool specimens or in tissue collected during endoscopy. Cysts are less frequently encountered. Balantidium coli trophozoites Balantidium coli trophozoites their large size (40 µm to more than 70 µm). their large size (40 µm to more than 70 µm). the presence of cilia on the cell surface, the presence of cilia on the cell surface, a bean shaped macronucleus which is often visible, a bean shaped macronucleus which is often visible, a smaller, less conspicuous micronucleus. a smaller, less conspicuous micronucleus.

54. Naegleria fowleri - Acanthomoeba spp commonly found in lakes, swimming pools, tap water, and heating and air conditioning units. commonly found in lakes, swimming pools, tap water, and heating and air conditioning units. only one species of Naegleria is known to infect humans, several species of Acanthamoeba are implicated only one species of Naegleria is known to infect humans, several species of Acanthamoeba are implicated

56. Symptoms Acute primary amebic meningoencephalitis (PAM) - Naegleria fowleri. Acute primary amebic meningoencephalitis (PAM) - Naegleria fowleri. severe headache and other meningeal signs, fever, vomiting, and focal neurologic deficits, and progresses rapidly (<10 days) and frequently to coma and death. severe headache and other meningeal signs, fever, vomiting, and focal neurologic deficits, and progresses rapidly (<10 days) and frequently to coma and death. Acanthamoeba spp. - subacute or chronic granulomatous amebic encephalitis (GAE), with a clinical picture of headaches, altered mental status, and focal neurologic deficit, which progresses over several weeks to death. Acanthamoeba spp. - subacute or chronic granulomatous amebic encephalitis (GAE), with a clinical picture of headaches, altered mental status, and focal neurologic deficit, which progresses over several weeks to death. granulomatous skin lesions granulomatous skin lesions more seriously, keratitis and corneal ulcers following corneal trauma or in association with contact lenses. more seriously, keratitis and corneal ulcers following corneal trauma or in association with contact lenses.

57. Diagnosis Naegleria infections CSF CSF a wet mount may detect motile trophozoites, a wet mount may detect motile trophozoites, Giemsa-stained smear trophozoites Giemsa-stained smear trophozoites Acanthamoeba infections, biopsy specimens (brain tissue, skin, cornea) or of corneal scrapings, which may detect trophozoites and cysts. biopsy specimens (brain tissue, skin, cornea) or of corneal scrapings, which may detect trophozoites and cysts. cultivation cultivation direct immunofluorescent antibody direct immunofluorescent antibody

58. N.fowleri Acanthomoeba spp.

59. Treatment Eye and skin infections caused by Acanthamoeba spp. are generally treatable. Topical use of 0.1% propamidine isethionate (Brolene) plus neomycin-polymyxin B-gramicidin ophthalmic solution Eye and skin infections caused by Acanthamoeba spp. are generally treatable. Topical use of 0.1% propamidine isethionate (Brolene) plus neomycin-polymyxin B-gramicidin ophthalmic solution keratoplasty is often necessary in severe infections keratoplasty is often necessary in severe infections Amphotericin B has been successfully used to treat PAM caused by Naegleria fowleri Amphotericin B has been successfully used to treat PAM caused by Naegleria fowleri

60. Sporozoans Blood sporozoans Blood sporozoans Plasmodium vivax Plasmodium vivax Plasmodium malariae Plasmodium malariae Plasmodium ovale Plasmodium ovale Plasmodium falciparum Plasmodium falciparum Babesia microti Babesia microti Other Other Isospora belli Isospora belli Sarcocystis bovihumanis Sarcocystis bovihumanis Cryptosporidium parvum Cryptosporidium parvum Toxoplasma gondii Toxoplasma gondii

61. Plasmodium spp. Plasmodium vivax Plasmodium vivax Plasmodium malariae Plasmodium malariae Plasmodium ovale Plasmodium ovale Plasmodium falciparum Plasmodium falciparum

62. A single species, P. reichenowi, which infects chimpanzees, is known to be a close sister lineage of P. falciparum. A single species, P. reichenowi, which infects chimpanzees, is known to be a close sister lineage of P. falciparum. This new species has been isolated in two chimpanzees (Pan troglodytes) kept as pets by villagers in Gabon (Africa). This new species has been isolated in two chimpanzees (Pan troglodytes) kept as pets by villagers in Gabon (Africa). The risk of transfer and emergence of this new species in humans must be now seriously considered given that it was found in two chimpanzees living in contact with humans and its close relatedness to the most virulent agent of malaria. The risk of transfer and emergence of this new species in humans must be now seriously considered given that it was found in two chimpanzees living in contact with humans and its close relatedness to the most virulent agent of malaria.

68. The malaria parasite life cycle involves two hosts. The malaria parasite life cycle involves two hosts. a malaria-infected female Anopheles mosquito - sporozoites - the human host sporozoites infect liver cells - into schizonts, which rupture and release merozoites. a malaria-infected female Anopheles mosquito - sporozoites - the human host sporozoites infect liver cells - into schizonts, which rupture and release merozoites. P. vivax and P. ovale a dormant stage [hypnozoites] can persist in the liver and cause relapses by invading the bloodstream weeks, or even years later. P. vivax and P. ovale a dormant stage [hypnozoites] can persist in the liver and cause relapses by invading the bloodstream weeks, or even years later. initial replication in the liver (exo-erythrocytic schizogony )-asexual multiplication in the erythrocytes (erythrocytic schizogony ). initial replication in the liver (exo-erythrocytic schizogony )-asexual multiplication in the erythrocytes (erythrocytic schizogony ). merozoites infect red blood cells. merozoites infect red blood cells. the ring stage trophozoites mature into schizonts, which rupture releasing merozoites. the ring stage trophozoites mature into schizonts, which rupture releasing merozoites. some parasites - into sexual erythrocytic stages (gametocytes). some parasites - into sexual erythrocytic stages (gametocytes).

69. male (microgametocytes) and female (macrogametocytes), are ingested by an Anopheles mosquito during a blood meal. male (microgametocytes) and female (macrogametocytes), are ingested by an Anopheles mosquito during a blood meal. parasites’ multiplication in the mosquito - the sporogonic cycle. parasites’ multiplication in the mosquito - the sporogonic cycle. in the mosquito's stomach, the microgametes penetrate the macrogametes generating zygotes in the mosquito's stomach, the microgametes penetrate the macrogametes generating zygotes the zygotes in turn become motile and elongated (ookinetes) which invade the midgut wall of the mosquito where they develop into oocysts. the zygotes in turn become motile and elongated (ookinetes) which invade the midgut wall of the mosquito where they develop into oocysts. the oocysts grow, rupture, and release sporozoites, which make their way to the mosquito's salivary glands. the oocysts grow, rupture, and release sporozoites, which make their way to the mosquito's salivary glands. Inoculation of the sporozoites into a new human host perpetuates the malaria life cycle. Inoculation of the sporozoites into a new human host perpetuates the malaria life cycle.

70. Symptoms The most frequent symptoms fever fever chills, chills, headache, headache, myalgias, myalgias, arthralgias, arthralgias, weakness, weakness, vomiting, vomiting, diarrhea. diarrhea.

71. Other clinical features Other clinical features splenomegaly, splenomegaly, anemia, anemia, thrombocytopenia, thrombocytopenia, hypoglycemia, hypoglycemia, pulmonary or renal dysfunction, pulmonary or renal dysfunction, neurologic changes. neurologic changes. P. falciparum (cerebral malaria), P. falciparum (cerebral malaria), acute renal failure, acute renal failure, severe anemia, severe anemia, adult respiratory distress syndrome. adult respiratory distress syndrome. P. vivax - splenomegaly (with, rarely, splenic rupture), P. vivax - splenomegaly (with, rarely, splenic rupture), P. malariae -nephrotic syndrome. P. malariae -nephrotic syndrome.

72. Ring: early developmental stage of the asexual erythrocytic parasite; Ring: early developmental stage of the asexual erythrocytic parasite; Ring Trophozoite: next developmental stage of the asexual erythrocytic parasite; it has lost its "ring" appearance, and has begun to accumulate pigment Trophozoite: next developmental stage of the asexual erythrocytic parasite; it has lost its "ring" appearance, and has begun to accumulate pigment Trophozoite: Schizont: late developmental stage of the asexual erythrocytic parasite; it has begun its division into merozoites, and thus is characterized by the presence of multiple contiguous chromatin dots Schizont: late developmental stage of the asexual erythrocytic parasite; it has begun its division into merozoites, and thus is characterized by the presence of multiple contiguous chromatin dots Schizont: Gametocyte: sexual erythrocytic stage. Gametocyte: sexual erythrocytic stage. Gametocyte:

73. Ring with double chromatin dot Schüffner's dots

74. Gametocytes of P. vivax Schüffner's dots

75. Mature schizonts. Ruptured schizonts

76. Large, amoeboid trophozoites of P. vivax

77. P. ovale rings

78. Gametocytes

79. Schizonts of P. ovale

80. Trophozoites of P. ovale

81. Ring forms

82. Gametocytes

83. Schizonts of P. malariae

84. Mature trophozoites band forms and "basket" form

86. Gametocytes

87. Immature schizont in a thin blood smear. Mature schizont.

88. trophozoites

98. Treatment Quinine ( in chloroquine resistant P.falciparum) Quinidine (IV form of quinine) Chloroquine (acute attack) (prophylaxis) Mefloquine (prophylaxis in chloroquine resistant cases) Prymethamine-sulfadoxine (in chloroquine resistant P.falciparum)

99. Artemisinine (Qinghaosu) ( in chloroquine resistant P.falciparum) Tetracycline and doxycycline HalofantrineChloroguanide Primaquine (eliminates exo erythrocytic forms in the liver)

100. Prophylaxis Chloroquine 500 mgr per week starting 1-2 wks before travel, during travel and 4 wks post travel. Chloroquine resistant P.falciparum mefloquine 250 mgr.per week, 1week before,during travel and 4 wks post travel. Don’t use mefloquine during pregnancy.Treatment Chloroquine 1gr po,0.5 gr in 6 hrs, then 0.5gr.daily x 2d. Primaquine 26.3 mgr.po daily x14d. Check for severe G6PD deficiency. Chloroquine resistant P.vivax quinine sulphate 650 mgr +doxycycline 100 mgr.OR mefloquine 750 mgr.po, then 500 mgr. 12 hrs.later. for 7 days Chloroquine resistant P.falciparum quinine sulphate 325 mgr.+ doxycycline100mgr. for 7 days.

103. Babesiosis hemoprotozoan parasites of the genus Babesia Babesia microti and Babesia divergens easily be misdiagnosed as Plasmodium

105. Symptoms probably asymptomatic feverchillssweatingmyalgiasfatiguehepatosplenomegaly hemolytic anemia

106. Diagnosis detection of parasites in patients' blood IFAPCR

107. Cystoisosporiasis Cystoisospora belli (Isospora belli) Cystoisospora belli (Isospora belli)

109. Symptoms Acute, nonbloody diarrhea with crampy abdominal pain, which can last for weeks and result in malabsorption and weight loss. Acute, nonbloody diarrhea with crampy abdominal pain, which can last for weeks and result in malabsorption and weight loss. In immunodepressed patients, and in infants and children, the diarrhea can be severe. In immunodepressed patients, and in infants and children, the diarrhea can be severe. Eosinophilia may be present (differently from other protozoan infections). Eosinophilia may be present (differently from other protozoan infections).

110. Diagnosis Wet mount Wet mount UV UV Modified acid-fast Modified acid-fast Safranin stain Safranin stain

112. Sarcocystosis Sarcocystis bovihumanis Sarcocystis bovihumanis

114. Symptoms often asymptomatic and clear spontaneously. often asymptomatic and clear spontaneously. mild fever, mild fever, diarrhea, diarrhea, chills, chills, vomiting vomiting respiratory problems respiratory problems

116. Cryptosporodiosis Cryptosporidium parvum and Cryptosporidium hominis (formerly known as C. parvum anthroponotic genotype or genotype 1) are the most prevalent species causing disease in humans, Cryptosporidium parvum and Cryptosporidium hominis (formerly known as C. parvum anthroponotic genotype or genotype 1) are the most prevalent species causing disease in humans, infections by C. felis, C. meleagridis, C. canis, and C. muris have also been reported. infections by C. felis, C. meleagridis, C. canis, and C. muris have also been reported.

118. Symptoms asymptomatic infections to severe, life-threatening illness; asymptomatic infections to severe, life-threatening illness; incubation period is an average of 7 days (but can range from 2 to 10 days). incubation period is an average of 7 days (but can range from 2 to 10 days). Watery diarrhea Watery diarrhea dehydration, dehydration, weight loss, weight loss, abdominal pain, abdominal pain, fever, fever, Nausea Nausea vomiting. vomiting. In immunocompetent persons, symptoms are usually short lived (1 to 2 weeks); they can be chronic and more severe in immunocompromised patients, especially those with CD4 counts <200/µl. In immunocompetent persons, symptoms are usually short lived (1 to 2 weeks); they can be chronic and more severe in immunocompromised patients, especially those with CD4 counts <200/µl. While the small intestine is the site most commonly affected, symptomatic Cryptosporidium infections have also been found in other organs including other digestive tract organs, the lungs, and possibly conjunctiva. While the small intestine is the site most commonly affected, symptomatic Cryptosporidium infections have also been found in other organs including other digestive tract organs, the lungs, and possibly conjunctiva.

120. Oocysts in stool smears stained with modified acid-fast stain: A Cryptosporidium sp. B Cyclospora cayetanensis C Cystoisospora belli

121. Toxoplasmosis eating undercooked meat of animals harboring tissue cysts. eating undercooked meat of animals harboring tissue cysts. consuming food or water contaminated with cat feces or by contaminated environmental samples (such as fecal- contaminated soil or changing the litter box of a pet cat). consuming food or water contaminated with cat feces or by contaminated environmental samples (such as fecal- contaminated soil or changing the litter box of a pet cat). blood transfusion or organ transplantation. blood transfusion or organ transplantation. transplacentally from mother to fetus. transplacentally from mother to fetus. Toxoplasma gondii Toxoplasma gondii

123. asymptomatic infection. asymptomatic infection. cervical lymphadenopathy cervical lymphadenopathy a flu-like illness. a flu-like illness. In rare cases ocular infection with visual loss can occur. In rare cases ocular infection with visual loss can occur. Immunodeficient patients ; central nervous system disease central nervous system disease retinochoroiditis, retinochoroiditis, pneumonitis, pneumonitis, other systemic disease. other systemic disease. In patients with AIDS, toxoplasmic encephalitis is the most common cause of intracerebral mass lesions.

124. Congenital toxoplasmosis Congenital toxoplasmosis results from an acute primary infection acquired by the mother during pregnancy. results from an acute primary infection acquired by the mother during pregnancy. The incidence and severity of congenital toxoplasmosis vary with the trimester during which infection was acquired. The incidence and severity of congenital toxoplasmosis vary with the trimester during which infection was acquired. Ocular Toxoplasma infection, can be the result of congenital infection, Ocular Toxoplasma infection, can be the result of congenital infection,

125. Observation of parasites in patient specimens, such as bronchoalveolar lavage material from immunocompromised patients, or lymph node biopsy. Observation of parasites in patient specimens, such as bronchoalveolar lavage material from immunocompromised patients, or lymph node biopsy. Isolation of parasites from blood or other body fluids, by intraperitoneal inoculation into mice or tissue culture. Isolation of parasites from blood or other body fluids, by intraperitoneal inoculation into mice or tissue culture. Detection of parasite genetic material by PCR, especially in detecting congenital infections in utero. Detection of parasite genetic material by PCR, especially in detecting congenital infections in utero. Serologic testing is the routine method of diagnosis. (T.gondii IgM and IgG) Serologic testing is the routine method of diagnosis. (T.gondii IgM and IgG)