African Trypanosomiasis

African Trypanosomiasis

1. Summary

   • Sleeping sickness
   • T brucei group
     • Gambiense TbG
       • West + Central
       • Gradual
         • Human- Human
     • rhodesiense TbR
       • East + South
       • Rapid
         • Reservoir
           • Game
           • Cattle
   • Vector (transmission)
     • Tsetse fly
       • Painful bite
       • Rural woodlands + forest
     • Rarely
       • Bloodborne
       • Congenital
   • Locality
     • Sub Saharan
       • DR of Congo
       • South Sudan
       • Central African Rebuplic
   • Negelected Tropical Disease
   • misdiagnosis as psychosis after travel

2. Vector

   • Tsetse fly
     • warm+ Shaded
     • 1-6 mo
     • Low infctn rate
       • 2-3 per1000

3. Life cycle

   • 1. Fly bite + injects parasite
     • 2. Metacyclic trypomastigotes → BS trypomastigotes
       • 3. Multiply via binary fission
         • 4. Trypomastigotes in blood
           • 5. Fly bite + ingest parasite
             • 6. BS parasite→ procylic parasite@ tsetse fly midgut
               • multiply via binary fission
               • 7. Procyclic parasite leave midgut→ epimastigotes
                 • 8. multiply @ salivary glands epi→ metacyclic
         • Human Stages
     • Tsetse fly Stages

4. Signs and Symptoms

   • Signs
     • Chancre
       • localised erythema
       • Indurated
       • Tender
       • Lymphadenopathy
         • trypanosome move to nearby nodes → lymphadenitis
         • painless
         • soft
         • mobile nodes
         • Common in TbG
         • @ posterior cervical "Winterbottom's Sign"
       • Onset in days
         • up to 3 weeks
       • Common in TbR
     • Hepatosplenomegaly
       • Anaemia
       • abnormal LFT
   • Symptoms
     • Parasitaemia
       • Myalgia
       • Fever
       • Headache
       • Weightloss
       • Rash
       • Itch
   • Complications
     • CVS
       • Myocardits
       • Effusions
     • Endocrince
       • Hypothyroidism
       • Hypoadrenalism
     • CNS
       • Psychosis
       • Convulsions
       • Insomnia/somnalence
       • Hyper/Para thenesia
       • Tremors/Ataxia/Focal signs
     • General
       • Wasting
       • Malnutrition
       • Infections

5. Dx

   • Demonstration of Parasite
     • Aspiration of chancre
     • Blood Film
       • blood concentration technique
       • Quantitative Buffy coat
         • QBC
     • Bone marrow
     • CSF
       • Mandatory
       • xclude CNS
       • Microscopy for trypanosomes
       • WCC > 5
       • Morula cells of Mott
         • Big Eosinophillic Plasma cell contain IgM
     • Serology
       • Population screening
       • CATT (Card Agglutination Test)
   • Ddx
     • HIV
       • Toxoplasmosis in HIV
         • CD<400
     • TB
     • Meningitis
     • Lymphoma
     • CNS vasculitis
     • Psychiatric illness
   • Prognosis
     • Fatal without Tx

6. Staging

   • Stage 1 (Early)
     • No CNS involvements
     • Haemolymphatics
   • Stage 2 (Late)
     • CNS involvements

7. Tx

   • TbG
     • S1- Pentamidine
     • S2 - Eflornithine / ±Nifurtimox
   • TbR
     • S1- Suramin
     • S2- Melarsoprol
   • Steroids often used
   • SE common
   • 1-3 weeks

8. Control

   • Vector control
   • Population screening
   • Minimise contact
   • Prevention
     • aerial insecticide
     • Tsetse fly trap
     • insectiside impregnated screen
     • wild animal pop reduction
     • removal of woody vegetaion

Images and files in the map