[Pathophysiological and diagnostic aspects of Guillain-Barré syndrome]. / Syndrome de Guillain-Barré : physiopathologie et aspects diagnostiques.

Guillain-Barré syndrome (GBS) is the most common cause of acute neuropathy. It usually onset with a rapidly progressive ascending bilateral weakness with sensory disturbances, and patients may require intensive treatment and close monitoring as about 30% have a respiratory muscle weakness and about 10% have autonomic dysfunction. The diagnosis of GBS is based on clinical history and examination. Complementary examinations are performed to rule out a differential diagnosis and to secondarily confirm the diagnosis. GBS is usually preceded by an infectious event in ≈ 2/3 of cases. Infection leads to an immune response directed against carbohydrate antigens located on the infectious agent and the formation of anti-ganglioside antibodies. By molecular mimicry, these antibodies can target structurally similar carbohydrates found on host's nerves. Their binding results in nerve conduction failure or/and demyelination which can lead to axonal loss. Some anti-ganglioside antibodies are associated with particular variants of GBS: the Miller-Fisher syndrome, facial diplegia and paresthesias, the pharyngo-cervico-brachial variant, the paraparetic variant, and the Bickerstaff brainstem encephalitis. Their semiological differences might be explained by a distinct expression of gangliosides among nerves. The aim of this review is to present pathophysiological aspects and the diagnostic approach of GBS and its variants.

Cerebral venous thrombosis in a sub-saharan African country: A preliminary monocentric study of a 70 case series at the neurology department of Fann teaching hospital in Dakar - Senegal.

INTRODUCTION: Cerebral venous thrombosis (CVT) are underdiagnosed in sub-saharan Africa where publications are uncommon. Our study aim was to describe the CVT diagnostic and therapeutic features through a senegalese case series. PATIENTS AND METHOD: A monocentric retrospective and prospective study was conducted at the adult Neurology department of Fann Teaching Hospital in Dakar (Senegal), between January 01, 2013 and April 30, 2020. It had included all CVT cases diagnosed by neurovascular imaging. RESULTS: Seventy CVT cases were collected including 48 women (68.6%). The average age of the patients was 35.2±14 years. The main neurological signs were headache (92.8%) and motor deficit (41.4%), with subacute onset in 67.2% of cases. The superior sagittal sinus (54.3%) and the transverse sinus (38.6%) were the most affected with multiple involvements in 27 patients (38.6%). Thirty patients (42.8%) had indirect parenchymal signs such as venous infarction (15.7%), cerebral edema (11.4%) or intracerebral hemorrhage (12.8%). The etiological factors were mostly infectious (41.4%) with meningoencephalitis (12.8%) and otorhinolaryngological infection (10%). Gyneco-obstetric factors (27%) and Behçet's disease (7%) were the main aseptic factors. In the short-term clinical course, curative anticoagulation (98.6%) had enabled a favourable outcome (mRS 0-1) in half of the patients. CONCLUSION: Our study, the largest series in sub-saharan Africa to this date, confirms that CVT is a young women disease. Infectious etiology is the most frequent at the Fann national teaching hospital (41.4% in Dakar against 6.5% in Germaine Bousser's series) even if the etiological assessment is limited by financial constraints (no coagulopathy/thrombophilia check-up).

[Neuro-Behçet in a Sub-Saharan Africa Country: a Series of Sixteen Patients in Fann Teaching Hospital, Dakar, Senegal]. / Neuro-Behçet dans un pays d'Afrique subsaharienne : une série de 16 patients au centre hospitalier national universitaire de Fann de Dakar, Sénégal.

Neuro-Behçet (NB) African studies are mainly North African, but Sub-Saharan Africa is not to be outdone. Our aim was to describe diagnostic and therapeutic features of NB in a Senegalese series collected in Dakar. This was a descriptive and retrospective study conducted at the Neurology department of Fann Teaching Hospital in Dakar, Senegal. All patients who met the NB's diagnostic criteria were included. Sixteen patients were collected, 14 males and 2 females with an average age of 40 years [18-71]. The main neurological signs were motor deficit (13 cases), headache (10 cases), and language disorders (4 cases). Extra-neurological signs were dermatological (14 cases), ocular (2 cases), and articular (2 cases) with aseptic unilateral gonarthritis. Fever was present in 9 patients. Neurological involvement was mostly isolated parenchymal (8 cases) or mixed (6 cases). The main clinical forms of NB were rhombencephalitis (8 cases) and retrobulbar optic neuritis (4 cases). Seven patients had a cerebral angio-Behçet with cerebral venous thrombosis (3 cases), ischemic stroke (2 cases), and intracerebral hematoma (2 cases). Under prednisone (16 cases) and azathioprine (3 cases), the short-term clinical outcome was mostly favorable (14 cases) with a modified Rankin scale at 2. NB is an under-diagnosed adult male disease in Sub-Saharan Africa and further studies are needed.

Les études africaines sur le neuro-Behçet (NB) sont majoritairement maghrébines, mais l'Afrique noire n'est pas en reste. L'objectif de l'étude était de décrire les particularités diagnostiques et thérapeutiques du NB dans une série sénégalaise colligée à Dakar. Il s'agit d'une étude rétrospective à visée descriptive menée à la clinique de neurologie du centre hospitalier universitaire de Fann de Dakar, au Sénégal. Tous les patients répondant aux critères diagnostiques de NB ont été inclus. Seize patients ont été colligés, 14 hommes et deux femmes avec un âge moyen de 40 ans [18­71]. Les principaux signes neurologiques étaient un déficit moteur (13 cas), des céphalées (10 cas) et un trouble du langage (4 cas). Les signes extraneurologiques étaient dermatologiques (14 cas), oculaires (2 cas) et articulaires (2 cas) à type de gonarthrite unilatérale aseptique. Une fièvre était présente chez neuf patients. L'atteinte neurologique était majoritairement parenchymateuse isolée (8 cas) ou mixte (6 cas). Les principales formes cliniques de NB étaient la rhombencéphalite (8 cas) et la névrite optique rétrobulbaire (4 cas). Sept patients avaient un angio-Behçet cérébral à type de thromboses veineuses cérébrales (3 cas), d'infarctus cérébraux (2 cas) et d'hématomes intracérébraux (2 cas). Sous prednisone (16 cas) et azathioprine (3 cas), l'évolution clinique à court terme était majoritairement favorable (14 cas) avec un score de Rankin modifié de 2 au moment de l'exeat. Le NB est une maladie de l'homme adulte sous-diagnostiquée en Afrique noire. Des études ultérieures multicentriques nationales et sous-régionales sont souhaitables.