Detection of Mycobacterium leprae in nerve lesions by the polymerase chain reaction.

A simple procedure is described for the detection of Mycobacterium leprae by the polymerase chain reaction in nerve biopsies sectioned with a cryostat and then treated with proteinase K. All samples from lepromatous leprosy patients and the majority of samples from paucibacillary cases yielded positive results. This approach may be useful for differentiating between leprosy and other inflammatory neuropathies.

[Lesions of the spinal cord in HIV infection]. / Atteintes de la moelle épinière au cours de l'infection par le VIH.

Neurological lesions are frequent complications of human immunodeficiency virus (HIV) infections. Organs involved include the brain, peripheral nerves and muscles. Since the widespread use of immunodepressive agents, spinal cord complications have also appeared although poorly documented in the literature. We observed six cases of spinal cord involvement which help indicate the modalities of practical management. In the first case, a 45-year old HIV1 + male presented dysesthesia evolving progressively over the T10 to L2 zones leading to the diagnosis of spinal cord toxoplasmosis. A gait disorder was the first sign in the second case, a 60-year old HIV1 + male. Neurological involvement progressed and the patient developed paraparesia, decreased muscular force with hypoesthesia and impaired proprioception of the lower limbs. Further complications led to coma and death and on autopsy, the patient was found to have cytomegalovirus myeloencephalitis. A 21 HIV1 + haemophiliac was our third case. Here paraplegia resulted from epidural compression due to Burkitt malignant lymphocytosis. The aggravation of paresthesia of the lower limbs, complicated by painful dysesthesia and proximal motor deficiency led to the suspected diagnosis of HIV-related myelitis in a particularly complicated case in a 52-year old seropositive male. In the fifth case, HIV infection led to major demelinization of the cervical and dorsal spinal cord due to toxoplasmosis and vacuolar myelopathy. In the sixth case, acute myelitis in an HIV2 positive male regressed spontaneously in 15 days. In clinical practice, spinal cord complications would appear to be frequent but less so than brain involvement. In the future, a better understanding of these complications should lead to specific identification of spinal cord signs in the neurological symptomatology of patients with HIV infection and allow adapted specific management.

[Spinal subdural hematoma. Presentation of 2 cases studied with MRI]. / Hématomes sous-duraux rachidiens. Présentation de deux cas explorés en IRM.

Spinal subdural hematomas are rare. They should be considered in the diagnosis of spinal cord compression. Prompt surgical treatment, if it is performed, may lead to complete recovery of the neurological deficit. But such treatment is not always necessary because of possible spontaneous recovery. MRI appears to be the method of choice to reveal hematomas even of small size and to follow up patients after treatment.

Ischaemic myelopathy secondary to disseminated intravascular coagulation in AIDS.

A 39-year-old patient with AIDS presented with a rapidly progressive myelopathy with a partial Brown-Séquard syndrome. He died, 9 weeks after onset of the first neurological signs, from diffuse encephalopathy. Neuropathological examination revealed multiple, usually small, frequently haemorrhagic, infarcts or various ages and numerous fibrin thrombi in medium and small penetrating vessels and capillaries of the brain and spinal cord, characteristic of disseminated intravascular coagulation. There were no inflammatory changes. Immunohistochemical studies for human immunodeficiency virus, cytomegalovirus, varicella zoster virus, herpes simplex virus type 1 and type 2 were negative. Ischaemic spinal cord lesions due to disseminated intravascular coagulation may represent an unusual cause of focal, non-inflammatory, non-tumoral, myelopathic syndrome in AIDS.

Cytomegalovirus neuropathy in acquired immunodeficiency syndrome: a clinical and pathological study.

We have observed typical cytomegalovirus cytopathology associated with multifocal inflammatory and necrotic lesions of peripheral nerve in biopsy specimens from 4 patients who developed a rapidly progressive, multifocal neuropathy late in the course of human immunodeficiency virus infection. The inflammatory infiltrates, which contained numerous polymorphonuclear cells, were associated with mixed, axonal, and demyelinative lesions of nerve fibers. One of these patients improved on treatment with DHPG (9-[2-hydroxy-l(hydroxymethyl) ethoxymethyl] guanine) and remains stable after 18 months. The other 3 died soon after the onset of the neuropathy. In another patient with acquired immunodeficiency syndrome, who developed a severe, predominantly motor neuropathy of the lower limbs, the nerve biopsy did not reveal cytomegalovirus inclusions, but the neurological deficit improved on treatment with DHPG. The patient died from cachexia 2 months later; numerous cytomegalovirus lesions were found in the spinal cord at the time of postmortem examination. The multifocal necrotic endoneurial nerve lesions with polymorphonuclear cell infiltration we describe may help identify cytomegalovirus neuropathy when characteristic inclusions are not present in the biopsy specimen.

[Lateral inferior pontine infarction: 2 clinical aspects]. / Infarctus pontin inférolatéral: deux aspects cliniques.

Cases of lateral inferior pontine infarction are rare in the literature. We report two cases with MRI correlations. One involved the whole territory, the other the tegmental area only. Both also involved the middle cerebellar peduncle and one of them the adjacent lobules of the cerebellum. The first case emphasizes the classical alternate syndrome. The second case shows that acute vertigo mimicking a labyrinthine lesion can occur when involving the territory of the anterior inferior cerebellar artery.

[Late neurosyphilis: a current disease]. / Neurosyphilis tardive: maladie d'actualité.

We report 7 cases of neurosyphilis observed over a 13-month period in a Parisian University Hospital. Four patients had meningo-encephalitis and 3 had arteritis with meningitis. Serology for the human immuno-deficiency virus was negative in all cases. The problems raised by the interpretation of serological data are discussed and the criteria of progressive neurosyphilis are underlined.

Allosteric effects of diprobutine on acetylcholine receptors.

The nicotinic effects of a novel antiparkinsonian compound, diprobutine were investigated on the acetylcholine receptor (AChR) from Torpedo marmorata electric organ and on rat brain membranes by a variety of techniques including stopped flow measurements. On the nicotinic AChR from Torpedo, diprobutine behaved as a typical noncompetitive blocker: it inhibited the agonist-regulated 22Na+ efflux from excitable microsacs; it shifted in the ms-s time-range the conformation of the AChR towards a high affinity state for agonists; it competed with [3H]PCP bound to its high affinity 'allosteric' site. On rat brain membrane, it displaced [3H]PCP bound to its high affinity site. The pharmacological properties of diprobutine are discussed in the context of its biochemical effects.

Acetylcholine receptor: an allosteric protein.

The nicotine receptor for the neurotransmitter acetylcholine is an allosteric protein composed of four different subunits assembled in a transmembrane pentamer alpha 2 beta gamma delta. The protein carries two acetylcholine sites at the level of the alpha subunits and contains the ion channel. The complete sequence of the four subunits is known. The membrane-bound protein undergoes conformational transitions that regulate the opening of the ion channel and are affected by various categories of pharmacologically active ligands.