Case report: an area postrema syndrome revealing a neuromyelitis optica spectrum disorder associated with central nervous system tuberculosis in a young Togolese (black African) woman.

BACKGROUND: Area postrema syndrome (APS) is considered to be one of the most specific clinical presentations of neuromyelitis optica spectrum disorders (NMOSDs). In sub-Saharan Africa, NMOSDs and even more so those revealed by an APS, are rarely reported. However, studies among mixed populations have shown that NMOSDs disproportionately affect black people with relatively more frequent encephalic involvement. We report a case of APS revealing an NMOSD associated with central nervous system (CNS) tuberculosis in a young Togolese woman residing in Togo (West Africa). CASE PRESENTATION: A 28-year-old Togolese woman was admitted for left hemibody sensory problems with ataxia. These problems were observed while the patient was hospitalized for a few days in the hepato-gastroenterology department for persistent vomiting, abdominal pain and hiccups lasting for about a month. The examination confirmed left hemibody ataxia with nystagmus when looking to the left, pronounced left osteotendinous reflexes, and left hemibody hypoesthesia up to the base of the neck. Encephalic magnetic resonance imaging (MRI) showed a hypersignal lesion in the bulbar more lateralized on the left in the fluid-attenuated inversion recovery sequence, not enhanced after a gadolinium injection. Biological assessment showed the presence of Mycobacterium tuberculosis deoxyribonucleic acid in the cerebrospinal fluid and a sedimentation rate of 120 mm in the 1st hour. The result of the anti-AQP4 antibody test was positive. Two months from the onset of digestive problems with Lhermitte's sign and hand and foot contracture access without vesico-sphincter problems were established. Cervical medullary MRI showed an additional intramedullary hypersignal lesion in the T2 sequence at the C2 level, not enhanced after a gadolinium injection. A second course of intravenous corticosteroids was administered, and anti-tuberculosis treatment was continued. The outcome was favorable. After 8 months of anti-tuberculosis treatment, the patient started immunosuppressive therapy (azathioprine 50 mg twice daily) to limit the risk of recurrence of NMOSD. CONCLUSION: The recognition of an APS is an additional challenge for the diagnosis of NMOSDs, especially in countries with limited resources. CNS tuberculosis must be tested when faced with an NMOSD because it seems to be a major cause.

Neuromyelitis Optica Spectrum Disorders in Black African: Experience of Togo (2015-2020).

Introduction Neuromyelitis optica spectrum disorders (NMOSD) would disproportionately affect blacks within mixed populations. However, they are rarely reported in black African. The objective of this work was to report the experience of Togo, a West African country in terms of NMOSD. Methods This is a series of six cases diagnosed between 2015 and 2020 in the only three neurology departments in Togo. The diagnosis of NMOSD was made according to the criteria of the International Panel for NMO Diagnosis (2015) and the patients had a minimum clinical follow-up of 6 months after the diagnosis. The search for anti-aquaporin 4 (AQP4) antibodies was performed by immunofluorescence on transfected cells. Results The mean age was 25.33 years and the sex ratio female/male was 5/1. The average time between the first attack and the diagnosis was 122.83 days. Clinically, there was isolated medullary involvement (2/6), simultaneous opticomedullary involvement (3/6), and area postrema syndrome (1/6). Five patients were anti-AQP4 positive. All six patients had extensive longitudinal myelitis. At 6 months of follow-up, there was one case of death and one case of blindness. Conclusion The rarity of NMOSD cases in Togo could be linked to an underestimation. To better characterize the NMOSDs of the black African population, multicenter and multidisciplinary studies are necessary.