LU 3.2ai Parasitic Infections of Blood and Lymphatic Systems

What is Schistosomiasis (Bilharzia) and its pathogen?

• is a water borne disease

• Schistosoma sp. (Blood Flukes)

What are the species of Schistosoma sp. and what are the risk factors?

• Schistosoma mansoni

• Schistosoma japonicum

• Schistosoma haematobium

• Risk factors : poor living condition, people who do fishing for livelihood, women use water for daily chores

Explain the life cycle for each species of Schistosoma species

• S. japonicum : 2 hours to reach the dermis and dermal blood vessel, produce 3000 eggs

• S. mansoni and S. haematobium : 48 hours to reach dermis, 72 hours to reach dermal blood, produce 300 eggs

Explain the pathophysiolgy/effects of acute schistosomiasis

• mostly asymptomatic

• lead to cercarial dermatitis

• stimulate hypersensitivity reaction that causes Katayama fever, fatigue, headache, cough

Explain the pathogenesis/sign and symptoms of chronic schistosomiasis/ each type of the Schistosomiasis sp.

• symptoms present months or years later

• S. mansoni and S.japonicum : abdominal pain, bloody diarrhea

• S. haematobium : dysuria, haematuria, ulcers, bladder cancer

What is the laboratory diagnosis for Schistosomiasis ?

Microscopy

What are the prevention and control for Schistosomiasis?

• Intervention of mass treatment (praziquantel, albendazole) for at-risk groups

• Treat water supply with chemicals to reduce intermediate hosts

• Draining fields through canals to control snails

What are the examples of haemoflagellates?

• Trypanosoma species

• Leishmania species

What are the examples of trypanosoma species?

• Trypanosoma cruzi

• Trypanosoma brucei

What is the disease caused by Trypanosoma cruzi and explain the pathogenesis / signs & symptoms of each phases

• Chagas disease

• the main reservoir host is rodents

• Initial phase : s/s :(first sign with skin lession at biting sites), parasites circulate in blood

• Chronic phase : s/s : (thickening of intestinal wall, progressive dilation, degenerative of neurons), parasites in heart, lead to death due to heart failure

What are the diseases caused by each types of Trypanosoma brucei?

• Trypanosoma brucei : African sleeping sickness

• Trypanosoma brucei gambiense : West African (Gambian) sleeping sickness

• Trypanosoma brucei rhodesiense : East African (Rhodesian) sleeping sickness

What are the sign & symptoms & effects for each trypanosoma brucei disease?

• T. brucei (African Sleeping Sickness) : i) early phase, parasites in blood circulation (s/s : headache, fever, chills), ii) second stage, parasites infects CNS (effects : confusion, sensory disturbance, death)

• T. brucei gambiense (West African (Gambian) Sleeping Sickness) : i) s/s: headcahe, weight loss ii)effects : daytime sleepiness with nightime sleep disturbance, coma

• T. brucei rhodesiense (East African (Rhoden) Sleeping Sickness) : i) s/s (fever, headace, enlarged lymph node) ii) effects (mental deterioration, death)

What are the laboratory diagnosis for Trypanosoma species

• Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense : peripheral blood, bone marrow, lymph nodes

• Trypanosoma cruzi : peripheral blood or tissue biopsy

• serological test for detecting antibodies (for screening purpose only)

What are the drug treatment for african sleeping sickness and Chagas disease?

• African Sleeping Sickness : Pentamidine, Melarsoprol, Eflornithine

• Chagas disease : Benznidazole

What are the prevention and control used for African Sleeping Sickness and Chagas disease?

• African Sleeping Sickness : Use insect repellents, vector control

• Chagas disease : insecticides spraying in houses, house improvement with no cracks in the walls

What are the pathogen of Leishmaniasis and its type?

• Pathogen : Leishmania sp.

• Three types :

• i) Visceral leishmaniasis (Leishmania donovani)

• ii) Cutaneous leishmaniasis (Leishmania tropica)

• iii) Mucocutaneous leishmaniasis (Leishmania braziliensis complex)

What are the risk factors of Leishmaniasis ?

• Weak immune system

• Poor housing

• Malnutrition

• Deforestation

• Building of dams

What are the symptoms, incubation period and diseases caused by Visceral leishmaniasis?

• Symptoms : fever, weight loss

• Incubation period : 3-8months

• Diseases : “Kala azar” (black disease), Dum Dum fever

What are symptoms and incubation period for cutaneous leishmaniasis?

• Symptoms : starts as papules at biting sites, increased in size, crust and ulcerates

• Incubation period : 2-8 weeks (New World)

What are the effects and incubation period of mucocutaneous leishmaniasis?

• effects : difficulty in eating and increase risk of secondary infections

• incubation period : 1-3 months

What are the laboratory diagnosis done for Leishmaniasis?

• biopsy samples

• Tissue culture

• Leishmania antibody detection

What are the prevention and control used for Leishmaniasis?

• spraying houses with insecticides

• use bednets

• effective treatment of patients combined with vector control