Molecular diagnosis of Rickettsia infection in patients from Tunisia.

Diagnosis of rickettsioses had largely benefited from the development of molecular techniques. Unfortunately, in Tunisia, despite the large number of rickettsial cases registered every year, the Rickettsia species remain unidentified. In this study, we aimed to detect the Rickettsia species in clinical samples using molecular tests. A study was established to analyze skin biopsies, cutaneous swabs, and cerebrospinal fluid samples taken from clinically suspected patients to have rickettsial infection. Two molecular techniques were used to detect Rickettsia DNA: quantitative real time PCR (qPCR) and reverse line blot test (RLB). An analysis of the RLB hybridization assay results revealed the presence of Rickettsia DNA in skin biopsies (40.6%) and swabs (46.7%). Rickettsia conorii was the most prevalent identified species among tested samples. Other species of interest include Rickettsia typhi and Rickettsia massiliae. Using qPCR positivity rates in skin biopsies was 63.7% against 80% in swabs. R. conorii was the most frequently detected species, followed by R. typhi. The agreement between the two techniques was 68.6% (kappa=0.33). Molecular tests, especially using specific probes qPCR, allow for a rapid, better and confident diagnosis in clinical practice. They improve the survey of Mediterranean spotted fever which is considered to be the most important rickettsial infection in humans in Tunisia.

[Transverse myelitis revealing Hodgkin disease]. / Myélite transverse révélant une maladie de Hodgkin.

INTRODUCTION: Neurological complications during Hodgkin disease are rare and sometimes difficult to diagnose. We report the case of a patient with transverse myelitis. CASE: This 32-year-old man was hospitalized on month after onset of febrile spastic paraplegia, which was accompanied by progressive deterioration of his general condition. Examination revealed a febrile, conscious patient, with abolition of the lower-limb tendon reflexes, bilateral Babinski signs, and sensitivity at D6-D7. We also noted hepatosplenomegaly, but no peripheral adenopathies. Laboratory reports indicated bicytopenia, a major inflammatory syndrome and hepatic cytolysis. The computed tomography examination of thorax and abdomen showed swelling in deep lymph nodes and the brain MRI showed what appeared to be transverse myelitis. The brainstem biopsy was normal; the hepatic biopsy showed liver infiltration by Sternberg cells. The patient died rapidly, before treatment could begin. DISCUSSION: The variable neurological events observed during Hodgkin disease may serve to reveal this disease. Their association with a tumor suggests this diagnosis even when the neurological signs are nonspecific. They may affect either the brain or the brainstem. Diagnostic certainty requires histologic analysis, and prognosis depends on early diagnosis and management.