Ischemic strokes revealing neurosyphilis: Study of six (6) observations at the neurology Department of the University Hospital of Conakry.

Introduction: In sub-Saharan Africa (SSA), stroke is a major public health problem and the etiological aspects are poorly studied and documented because of under-medicalization; the syphilitic etiology is rarely mentioned. Patients and methods: We performed a retrospective study of 472 patients hospitalized for ischemic stroke between 2016 and 2021 in the Neurology Department of the University Hospital of Conakry, confirmed by neuroradiological explorations (brain CT, MRI-Angio) and a biological workup including VDRL-TPHA serological reactions in blood and CSF. Results: Syphilitic etiology was retained for six (6) patients (4 men and 2 women) with a mean age of 43 years (extremes 36 and 49 years). The clinical picture was dominated by carotid syndromes: superficial and deep sylvian syndrome, anterior cerebral artery syndrome and vertebro-basilar syndromes and one case of lacunar syndrome.The diagnosis was based on the positivity of serological reactions (VDRL-TPHA) in blood and cerebrospinal fluid (CSF) and the presence of a predominantly lymphocytic hypercellularity and a hyperproteinorachy in the CSF in the absence of any other etiology. Conclusion: These neurological vascular syndromes consecutive to a cerebral treponematous attack are often the result of a still poorly conducted management of primary and secondary syphilis in our country.

[Frequency of drug resistance and immune escape mutations in the hepatitis B virus genome detected in pregnant women in the Republic of Guinea].

The aim of the work is to assess the prevalence of hepatitis B virus drug resistance mutations and immune escape mutations in pregnant women in the Republic of Guinea. MATERIALS AND METHODS: Blood plasma samples obtained from 480 pregnant women from different regions of the Republic of Guinea with laboratory-confirmed viral hepatitis B were studied. Nucleotide sequences for genotype identification and mutation detection were obtained using nested-PCR followed by Sanger sequencing, based on overlapping pairs of primers spanning the complete genome of the virus. RESULTS AND DISCUSSION: In the examined group, the viral genotype E was the most prevalent (92.92%) compared with subgenotypes A1 (1.67%), A3 (1.46%), D1 (0.63%), D2 (1.04%) and D3 (2.29%). Among the examined HBV-infected pregnant women, 188 (39.17%) had undetectable HBsAg. Drug resistance mutations were detected in 33 individuals, which amounted to 6.88%. The following mutations were found: S78T (27.27%), L80I (24.24%), S202I (15.15%), M204I/V (42.42%). The presence of polymorphic variants not described as drug resistant has also been shown in positions associated with the development of drug resistance to tenofovir, lamivudine, telbivudine and entecavir (L80F, S202I, M204R). When analyzing the MHR and the region of a determinant, mutations were detected in 318 (66.25%) of pregnant women. In 172 of them, which amounted to 54.09%, multiple mutations were found. The amino acid substitutions in 13 positions associated with HBsAg-negative hepatitis B and/or potentially affecting HBsAg antigenicity were identified. CONCLUSION: The high prevalence of immune escape and drug resistance mutations potentially associated with false-negative result of HBsAg screening, prophylaxis failure, and virological failure of therapy that has been identified among treatment naive pregnant women imposes a serious problem.

EPILEPTIC SEIZURES REVEALING STURGE WEBER'S DISEASE IN A TROPICAL ENVIRONMENT: STUDY OF EIGHT CASES.

In sub-Saharan Africa (SSA), the etiological factors of epilepsy are multiple and phacomatoses, in particular Sturge weber's disease, are rarely reported due to under-medicalization and insufficient multidisciplinary care. We carried out a retrospective study of 216 patients hospitalized for recurrent epileptic seizures between 2015 and 2022 in the neurology and pediatrics department of the University Hospital Center of Conakry, among whom eight (8) patients were identified for Sturge Weber's disease in order to reassess this pathology from a clinical and paraclinical point of view in a tropical environment. Sturge Weber's disease was retained in eight (8) on the presence of symptomatic partial epileptic seizures (age 6 months to 14 years) with frequency of status epilepticus, homonymous lateral hemiparesis linked to occipital involvement, piriform calcifications on imaging and ocular disorders. The delay in consultation and medical care revealed severe mental deterioration in our patients. This study shows a stereotyped clinical picture in a context of aggravation of signs related to a delay in multidisciplinary management. These results are important for the diagnostic, therapeutic and prognostic discussion.

[Prevalence of viral hepatitis B markers among blood donors in the Republic of Guinea].

INTRODUCTION: The problem of transfusion safety in relation to parenteral viral hepatitis still remains relevant. Viral hepatitis B (HB) remains the most common viral infection transmitted through transfusion procedures. One of the natural phases of chronic hepatitis B (CHB) is occult hepatitis B infection (OBI), characterized by an undetectable HBsAg (regardless of the other serological markers content) in the presence of hepatitis B virus (HBV) DNA in the liver tissue and an extremely low, up to undetectable, level of viral load in the blood. In the Republic of Guinea, as in most countries on the continent, the prevention of HBV transmission through transfusion is still based on HBsAg serological testing of donors only. In this connection, OBI remains as a potential threat to blood transfusion safety. Detection of HBV DNA is a reliable preventive measure against transmission of the virus from donors with HBsAg-negative HBV infection, especially in highly endemic regions. In this regard, the study was conducted to substantiate recommendations for improving blood safety against the background of significant HBV prevalence in the Republic of Guinea.The aim of the work was the evaluation of serological and molecular markers of HBV infection in blood donors in the Republic of Guinea. MATERIAL AND METHODS: We examined 250 blood samples obtained from donors living in Conakry, Republic of Guinea. Samples were tested for the presence of serological (surface antigen, HBsAg; antibodies (ABs) to surface (anti-HBs IgG) and core (anti-HBc IgG) antigens) and molecular (DNA) markers of HBV infection. RESULTS AND DISCUSSION: The overall detection rate of hepatitis B markers was 83.2%; HBsAg was detected in 16.4% of all individuals. The high incidence of HBsAg in men (19.55%) compared to women (8.45%) was shown, the relative risk of HBV infection with the formation of HBsAg-positive chronic hepatitis B in males was also significantly higher. The prevalence of the HBV DNA in the study group was 30.4%, the OBI cases accounted for 15.6%. The prevalence of this form of the disease was shown in donors aged 30-49 years (24.78%), in the group of people younger than 30 years, the incidence was lower (8.73%), and at the age of over 50 years, OBI was not detected. Based on the phylogenetic analysis of 76 virus isolates, it was shown that genotype E prevails in the examined group (85.53%).Cases of pathogen DNA detection occurred in HBsAg-negative blood donors in the presence of anti-HBs IgG (n = 4), as well as in the simultaneous presence of ABs anti-HBs IgG and anti-HBc IgG (n = 7). The viral load exceeded 200 IU/ml in OBI samples. Escape mutations were detected by sequencing in each OBI sample, contributing to the virus escaping from diagnostic based on screening for HBsAg. CONCLUSION: Assessment of the prevalence viral hepatitis B markers in blood donors, determination of genotypes and clinically significant mutations of virus variants are necessary to ensure safe medical manipulations, control and prevention of the spread of this infectious agent.