Alterations of Thymus Cortical Epithelium and Interdigitating Dendritic Cells but No Increase of Thymocyte Cell Death in the Early Course of Simian Immunodeficiency Virus Infection

The role of the thymus in the pathogenesis of simian acquired immunodeficiency syndrome was investigated in 18 juvenile rhesus monkeys (Macaca mulatto). The thymus was infected from the first week post-SIVmac inoculation, but the amount of virus-positive cells was very low (< 1 in 10⁴ T cells) as demonstrated by polymerase chain reaction and in situ hybridization. First morphological alteration was a narrowing of the cortex at 12 and 24 wpi. Morphometry revealed no increase of pyknotic T cells but a decrease of the proliferation rate and flow cytometry showed a reduction of the immature CD4⁺/CD8⁺ double-positive T cells. Ultrastructural analysis revealed vacuolization, shrinkage, and finally cytolysis of the cortical epithelial cells and the interdigitating dendritic cells. Immunofluorescence staining exhibited a widespread loss of cortical epithelial cells. This damage to the thymic microenvironment could explain the breakdown of the intrathymic T cell proliferation. It preceded fully developed simian acquired immunodeficiency syndrome and is therefore considered to play a major role in its pathogenesis.     

Development of a clinical and biological scoring system for the prognosis of Rift Valley fever

With regard to an acute disease, Rift Valley fever, we tried to establish a prognostic score to help physicians to set prognosis and to choose a health management suitable in their context. Using clinical and biological data collected during the 1987 RVF epidemic in Southern Mauritania, we established a prognosis score card. Data analysis allows to prognosticate forms of possible severe evolution as an association of four syndromes: fever over 39 degrees, hemorrhagic syndrome, icterus and neurological signs. Using 12 clinical symptoms and 3 biological signs, it is possible to prognosticate cases with fatal evolution.     

Conservative valve surgery in endomyocardial fibrosis. Apropos of 8 cases among 46 surgically treated patients

The authors report their experience of conservative valvular surgery in endomyocardial fibrosis (EMF) (8 cases among 46 surgical cases). These patients were divided into 3 groups: Group I: bilateral EMF predominating on the left side with associated tricuspid involvement (n: 3). Group II: bilateral EMF predominating on the right side with moderate associated mitral involvement (n: 3). Group III: unilateral EMF with massive mitral insufficiency, (n: 2). At surgery, on the side of the conserved valve, the patients had a transvalvular endocardectomy (n: 3) and a valvuloplasty either tricuspid (n: 3) or mitral (n: 5). The results of the valvuloplasty were satisfactory. Two patients died in the post-operative period. Their death was unrelated with the conservative procedure. The authors study the literature concerning the cases of valvular conservative surgery in EMF (n: 4) and define the conditions under which this surgery can be done. They report 2 original cases of pure left sided limited EMF with massive mitral insufficiency successfully treated by a valvuloplasty.     

épidémiologie clinique et parasitologique de la leishmaniose cutanée dans cinq villages du Pays Dogon, Mali

The epidemiology of the cutaneous leishmaniasis (CL) with Leishmania major is poorly documented in Mali. Following reports of CL in the tourist areas of the Dogon country (Bandiagara Escarpment), a joint French and Malian bio-clinical team conducted a field study from 16 to 27 January, 2010. The population of 5 villages has been examined by a dermato-infectiologist and cases were selected by visual inspection of skin lesions. Smears and biopsies (from the lesions) and venous blood were obtained from suspected cases of CL. Diagnosis was performed by light microscopy, in vitro cultures, serology and molecular biology. Fifty patients with skin lesions have been examined. Twenty-one have been suspected as CL. At least one sample was obtained from 18 patients. The lesions were predominantly old, more or less scarring and secondary infected. A skin smear was performed for 15 patients, a skin biopsy for 14 patients: smears and cultures were all negative. The PCR (Leishmania spp.) made on 14 biopsies was positive for 12 patients (86%). The low amount of amplified DNA obtained did not allow the sequencing and identification of the species of Leishmania. Western blot (WB) serology was positive in 11 cases out of 12 (92%). This investigation showed the presence of cutaneous leishmaniasis in Bandiagara. A further investigation is required during transmission period (September-October) to confirm the presence of Leishmania major epidemic in Dogon country.     

Morbidité et mortalité du tétanos dans le service de maladies infectieuses du CHU du Point G à Bamako, Mali (2004–2009)

Our study objectives were to determine annual cases of the tetanus and to describe its clinical, evolutionary and prognostic aspects. It was a transverse study from data records and medical records of patients aged 15 years and above hospitalized for tetanus in the service of infectious diseases of the Point G CHU from January 1, 2004 to December 31, 2009. The tetanus was diagnosed based on clinical (trismus, dysphagia, seizures and point consecutive to an injury) and epidemiological arguments (absence of a correct tetanus immunization, entry way). We collected a total of 119 cases of tetanus out of 1,839 hospitalizations making a prevalence of 6.5%. The hospitalization period was 5 days (73%) for most of the patients. Unskilled laborer and farmers were the most frequent with respectively 30.2 and 21.8% of cases. Tetanus occurred in the course of a traumatic road accident (16%) and from other traumatic causes (48.7%). The clinical form was a generalized type for 94.4% of the cases. A wound was the entry way for 64.7% of the patients. The entry way was located on the lower members 49.6% of the time. The co-morbidity was recorded with infection by Plasmodium falciparum (15 cases, 12.6%) and HIV (1 case). Hospital lethality was 46.2%. The death was statistically linked to clinical severity according to the Dakar score (P = 0.0005) and the Mollaret stage (P = 0.0001). A need for strengthening communication for behaviour change for the gaining of a correct and sustained immunization exists. A strategy based on the capacity building for a rapid tetanus diagnosis and a combined co-morbidities care may reduce the lethality in the context of our limited technical environment.     

Adult spinal cord injury with no radiographic bone lesion: analysis of nine consecutive patients

Background

Spinal cord injury with no radiographic bone lesion described as spinal cord injury without radiographic abnormality (SCIWORA) in childhood is less often reported in adults than in children. This study was undertaken to report our experience in the management of nine cases over 25 years.

Patients and methods

This was a retrospective study from 1985 to 2009 concerning nine adult patients who sustained spinal cord injury with no radiographic abnormality. The ratio among all cervical spine traumas for the same period was 2.21%. Magnetic resonance imaging (MRI) was performed in all the patients. The patients’ clinical status at the time of admission and discharge was evaluated using the Frankel's grading system. We report the results based on the clinical, epidemiologic and radiological findings and outcomes.

Results

The mean age of our population was 37.43 years, ranging from 18 to 60 years. All the patients were men. The main etiology was falls (5/9) followed by road traffic accidents (4/9). According to the Frankel's grading system, four patients (44.45%) were grade A, four were grade B (44.45%), and one was grade C (11.11%). On MRI, medullar lesions were: contusion, non-compressive cervical disc herniation, cervical spine stenosis, and two cases of normal cervical spine. Four patients were operated on via the posterior cervical spine approach (laminectomy, C3-C7 in three cases and C1-C3 in one case). The other five patients were treated orthopaedically for 6 to 8 weeks. Three patients (3/9), who were Frankel's grade B and C with no demonstrable injury on MRI, improved to Frankel a useful neurological grade (Frankel's grades D or E) at the time of discharge. One patient evaluated as Frankel's grade A died from cardiovascular disturbance.

Conclusion

Spinal cord injury with no radiographic abnormality accounted for 2.21% of cases of spinal cord injury in our series. MRI is the investigation of choice, having diagnostic and prognostic value because it demonstrates neural and extraneural injuries and helps to identify surgically correctable abnormalities.