Human African trypanosomiasis, also known as African sleeping sickness, is an illness caused by one of two parasitic zoonoses: Trypanosoma brucei gambiense or Trypanosoma brucei rhodesiense.
African trypanosomiasis is a disease endemic to sub-Saharan Africa. Within this region the disease is harbored mainly in rural areas 1, where access to medical imaging is often non-existent.Trypanosoma brucei gambiense accounts for the vast majority of reported cases of African trypanosomiasis. The incidence and prevalence have varied widely over the last two centuries. Under 3,000 cases were reported in 2016, and the incidence is declining 2.
In the initial stage of African trypanosomiasis, many symptoms of the disease are non-specific, such as fever and malaise. Untreated, the disease progresses to include various neurological manifestations, including encephalitis, coma, and ultimately death.
Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense are transmitted by certain species of the tsetse fly, although other transmission routes are possible 3.
There have been only small case series and case reports of brain MRI of patients with African trypanosomiasis at stage II (central nervous system involvement) 4-6.
- symmetric high signal intensity in the supratentorial deep white matter (all cases) 5
- high signal intensity in the basal ganglia, cerebellum, and/or brainstem (around half of cases)
- DWI: restricted diffusion may be seen in white matter tracts such as the posterior limbs of the internal capsules and splenium of the corpus callosum 5
- SWI/GRE/T2*: parenchymal microhemorrhages may be seen 5
- 1. Franco JR, Simarro PP, Diarra A, Jannin JG. Epidemiology of human African trypanosomiasis. (2014) Clinical epidemiology. 6: 257-75. doi:10.2147/CLEP.S39728 - Pubmed
- 2. Franco JR, Cecchi G, Priotto G, Paone M, Diarra A, Grout L, Simarro PP, Zhao W, Argaw D. Monitoring the elimination of human African trypanosomiasis: Update to 2016. (2018) PLoS neglected tropical diseases. 12 (12): e0006890. doi:10.1371/journal.pntd.0006890 - Pubmed
- 3. Rocha G, Martins A, Gama G, Brandão F, Atouguia J. Possible cases of sexual and congenital transmission of sleeping sickness. (2004) Lancet (London, England). 363 (9404): 247. doi:10.1016/S0140-6736(03)15345-7 - Pubmed
- 4. Gill DS, Chatha DS, del Carpio-O'Donovan R. MR imaging findings in African trypansomiasis. (2003) AJNR. American journal of neuroradiology. 24 (7): 1383-5. Pubmed
- 5. Patel NK, Clegg A, Brown M, Hyare H. MRI findings of the brain in human African trypanosomiasis: a case series and review of the literature. (2018) BJR case reports. 4 (4): 20180039. doi:10.1259/bjrcr.20180039 - Pubmed
- 6. Cherif Mohamadou Aidara, Caroline Magne, Philomene Kouna, Gaelle Ebinda Mipinda, Abdoulaye Dione Diop, Abdoulaye Ndoye Diop, Sokhna Ba. High Field MRI in Human African Trypanosomiasis (HAT). (2017) Open Journal of Radiology. 7 (3): 190. doi:10.4236/ojrad.2017.73021