Multiple nerve abscesses on cutaneous radial nerve--a case of pure neural leprosy.

Leprosy is a unique infectious disease due to varied spectrum of clinical signs it exhibits. Pure neural leprosy (PNL) is an unusual form of leprosy and accounts for 4-8% of all leprosy cases. It can manifest as a simple tingling sensation to complex and tragic motor paralysis. Here we report a case of PNL involving isolated cutaneous radial nerve as multiple abscesses along the course of the nerve. To the best of our knowledge, this is rarest presentation of pure neural leprosy.

[The painful multiple mononeuropathy of acute onset in the left arm which was diagnosed as leprous neuropathy].

A 31-year-old man from Myanmar with leprous neuropathy was reported. The progress of the disease was subacute but the painful symptom at the time of the onset was acute. Multiple mononeuropathy was diagnosed by the biopsy findings of the left superficial radial nerve. He was admitted to our hospital with the complaint of the weakness of his left hand and fingers which were very painful and got worse in several weeks. Motor palsy was observed in his left ulnar, median, and radial nerves, and there was the hypesthesia or anesthesia in his left hand, forearm and the medial side of his left upper arm. On nerve conduction studies, the amplitudes of CMAP and SNAP severely diminished or not detected. The pattern was compatible with multiple mononeuropathy. The biopsy of the left superficial radial nerve was performed. The pathological findings were the destruction of nerve fascicles, replacement of nerve fibers with inflammatory cells, and Mycobacterium leprae was found with the specific stain. These findings confirmed the diagnosis of the leprous neuropathy. Leprous neuropathy is one of the commonest causes of infectious neuropathy in the world, especially in Southeast Asia. These days many foreign workers from that area are staying in Japan, and the chances to see the disease are increasing. We have to recognize leprous neuropathy as a candidate for the multiple mononeuropathy of acute onset with painful dysesthesia similar to vascular neuropathy.

Light and electron microscopic study of peripheral nerve damage in patients with lepromatous leprosy (LL) and borderline lepromatous leprosy (BL).

Cutaneous branches of radial nerves in patients with lepromatous leprosy (LL) and borderline lepromatous (BL) were studied by light and electron microscopy. Foamy macrophages were found more or less in the nerve fibers of all leprosy patients and distributed in the epineurial, perineurial and endoneurial areas. In the endoneurium, the foamy macrophages were mainly located in the subperineurial and perivascular spaces. Vacuolated Schwann cells were also found in the nerve fasciculus. In electron microscopy, these foamy macrophages and vacuolated Schwann cells contained numerous small dense materials, irregular in size and shape, considered to be degenerated and fragmented mycobacterium leprae. These dense materials were found also in the cytoplasm of vascular endothelial cells. These findings suggest that mycobacteria enter into the endoneurium via the blood vessels. In our present study, on the other hand, it was very difficult to find the intact mycobacteria in the cytoplasm of the foamy macrophages, Schwann cells or endothelial cells, as well as in the Ziehl-Neelsen staining of paraffin sections. The disappearance of intact bacilli in our present study might have been caused by multi drug therapy. The myelinated nerve fibers were degenerated and disappeared in variable degrees. Degenerative changes of the myelin sheath developed from the outer layer to the inner layer with disarrangement of the lamellar structure. These findings were different from myelin destruction of peripheral nerves in Wallerian degeneration. The degenerative changes of the myelin sheath are caused by degeneration and destruction of Schwann cells in leprosy patients. Fibrosis surrounding myelinated and unmyelinated nerve fibers, i.e., periaxonal fibrosis, was found to a greater or lesser extent in the endoneurium. In the present study, it is still unclear whether the periaxonal fibrosis was due to necrosis of the Schwann cells by infection of mycobacteria or to an autoimmune mechanism such as antiperipheral nerve antibody. However, lamellated concentric fibrosis surrounding regenerative myelinated and unmyelinated nerve fibers with the disappearance of mycobacteria suggests that degenerations and regenerations of nerve axons were repeated during clinical cause. These findings indicated that autoimmune mechanisms play an important role in the pathogenesis of periaxonal fibrosis.

[Should biopsy be done on the sensory branch of the radial nerve in leprosy patients? Apropos of 112 cases]. / Doit-on pratiquer des biopsies de la branche sensitive du nerf radial chez les malades lépreux? A propos de 112 cas.

Biopsies of the superficial sensory branch of the radial nerve are contested. Some authors mention it to be simple and without harm, but others are formally against this procedure. At ILAD, 274 biopsies were made between 1986 to 1992. We present a review of 112 leprosy patients for whom biopsy was done. On 112 reexamined patients, we observed 2 benign neuroma, hence 2%. The comparison of nerve function before biopsy and after, of 63 of the 112 patients, reexamination shows no significant modification of the functional score. Given even the occurrence of benign neuroma in only 2% of the cases, the authors do not recommend the biopsy of the superficial sensory branch of the radial nerve. For research purposes on neuritis in leprosy, as well as to assure diagnosis in primary neuritic leprosy, we propose the biopsy of the sensory branch of the musculo cutaneous nerve at elbow level.

Inflammatory pseudotumor of nerve.

Two cases of inflammatory pseudotumor are described. The first patient, a 35-year-old white man, developed a progressive sensorimotor deficit in the right leg associated with a fusiform sciatic nerve mass in the posterior thigh. The lesion, compressive in nature and situated entirely within the epineurium, was totally resected. Histology revealed lymphocytic and plasmacellular inflammation as well as extensive fibrosis and collagen deposition. The patchy infiltrate consisted equally of CD2, CD3, CD5, and CD7 positive T-lymphocytes as well as CD20-and CD22-positive B-lymphocytes expressing both kappa and lambda immunoglobulin light chains. A selective biopsy of the encompassed and compressed nerve fascicles demonstrated both myelin loss and axonal injury. The second case was that of an 18-year-old woman with focal enlargement of a radial nerve by an epineurial infiltrate of multinucleate histiocytes and T as well as occasional B lymphocytes. No etiology was apparent in either case. The differential diagnosis includes non-neoplastic processes (amyloidoma and tuberculoid leprosy) as well as tumors (benign and malignant peripheral nerve sheath tumors, lymphoma). Although rare, inflammatory pseudotumors must be included in the differential diagnosis of tumor-like lesions of peripheral nerve.

Reaçäo hansênica tipo I na hanseníase borderline tuberculóide durante a poliquimioterapia: época de aparecimento e nervos acometidos / Type I reaction in borderline tuberculoid leprosy under multidrug therapy: time of onset and nerves affected

FUNDAMENTOS - A reaçäo tipo I é pouco estudada na literatura. OBJETIVOS - Descrever a época de aparecimento da reaçäo tipo 1 e os nervos acometidos, nos pacientes portadores de hanseníase borderline tuberculóide (BT), durante a poliquimioterapia(PQT). PACIENTES E MÉTODOS - Estudo longitudinal realizado no Ambulatório de Dermatologia da Faculdade de Medicina da UFMG. Setenta e um pacientes com hanseníase BT foram incluídos no estudo de agosto de 1989 a agosto de 1993. RESULTADOS - 89,3 por cento dos pacientes hansenianos BT com reaçäo tipo 1 apresentaram esse surto atá a sexta dose de tratamento. O nervo ulnar foi o mais acometido nas reaçöes tipo 1 (37,0 por cento). CONCLUSÃO - A reaçäo tipo 1 nos pacientes hansenianos BT ocorre mais frequentemente até a sexta dose de PQT. O nervo ulnar foi o mais acometido

Exame palpatório de nervos periféricos (espessados na hansenáse) e suas vias anatômicas / Palpations of peripheral nerves (thickened in leprosy) and their anatomical pathways

Este trabalho demonstra, por meio de dissecçäo, o trajeto superficial dos nervos comprometidos na hanseníase. Nessa doença, as lesöes ocorrem com mais frequência em determinados nervos que, nesses casos, se tornam mais espessos do que o normal. Esses nervos específicos säo superficiais em alguma parte de seus trajetos anatômicos e, aí, mais facilmente palpáveis

Asymptomatic nerve hypertrophy in lepromatous leprosy: a clinical, electrophysiological and morphological study.

In order to learn more about early nerve lesions observed in leprosy, we performed a clinical, electrophysiological and morphological study in seven patients with untreated lepromatous leprosy, palpably enlarged radial cutaneous nerve and preserved sensation in the corresponding territory. The conduction velocity of the cutaneous radial nerve, which was decreased in all patients, did not significantly differ from that of a group of patients with lepromatous leprosy, hypertrophy of the radial cutaneous nerve and sensory loss. In contrast, the sensory action potential was significantly lower in patients with sensory loss, which demonstrates that axon loss is more important than demyelination in producing sensory loss. In all patients nerve enlargement was due to thickening of the epineurium and of the perineurium subsequent to inflammatory infiltrates and proliferation of fibroblasts and perineurial cells. In several fascicles, the inflammatory infiltrates and the infected cells infiltrated endoneurial connective tissue septa and blood vessels. Mycobacteria leprae were abundant in perineurial cells, fibroblasts, macrophages, Schwann cells and endothelial cells, and lymphocytic vasculitis present in all cases. The average density of myelinated fibres was 2600 SD 880 fibres/mm2 (control: 7700 fibres/mm2), with marked differences between individual fascicles, versus 420 fibres/mm2 in patients with nerve hypertrophy and sensory loss (range 0-2080 fibres/mm2). Single fibre preparations showed that segmental demyelination predominated in two patients, axonal degeneration in one, while inflammatory infiltrates and proliferation of connective tissue adhering to individual fibres were prominent in the others.(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental borderline lepromatous leprosy with intraneural erythema nodosum leprosum in a mangabey monkey (Cercocebus atys).

A sooty mangabey monkey (Cercocebus atys) was inoculated with Mycobacterium leprae and developed borderline lepromatous leprosy and intraneural erythema nodosum leprosum. Previously studied mangabeys have developed only disseminated lepromatous leprosy without reactions. This case broadens the spectrum of leprosy seen in experimentally inoculated animals and further characterizes the nonhuman primate model of leprosy.

Isolation and characterization of infiltrates in the nerves of patients with neuritic leprosy.

A study was done on the characteristics of infiltrating cells in the nerves of 9 patients with pure neuritic leprosy, by preparing a single cell suspension. The patients had no skin lesion. Histopathological examination revealed that 2 of the 9 nerves showed granulomas characteristics of tuberculoid leprosy, while the remaining 7 had features of lepromatous granulomas. In the nerves showing tuberculoid granulomas, a high proportion of lymphocytes were T cells as they formed rosettes with sheep erythrocytes and only a few percent were EAC rosette forming cells. On the other hand, the nerves showing lepromatous granulomas contained only occasional lymphocytes which formed E and EAC rosettes. Macrophages from the granulomas of all the nerves were esterase positive, peroxidase negative, contained M. leprae and did not exhibit C3 surface receptors.

Isolation and characterization of cells in granulomas of nerves of leprosy patients.

Single cell suspension from the granulomas in nerves of leprosy patients were prepared for an in vitro study of the properties of infiltrating cells. Nerve biopsies from 17 patients with tuberculoid (n = 9) and lepromatous (n = 8) leprosy cases were analysed. The granulomas were found to contain lymphocytes and macrophages. Lymphocytes were the predominant infiltrating cells in the tuberculoid nerves. In contrast, lepromatous nerves contained very few of these cells. The majority of lymphocytes in tuberculoid granulomas were activated T cells as they formed rosettes with sheep erythrocytes, exhibited esterase dots in the cytoplasm and expressed HLA-DR antigens. A small proportion of the lymphocytes also formed rosettes with EAC. Most macrophages from both the granulomas were mature macrophages as they were esterase positive, did not exhibit peroxidase activity and expressed HLA-DR antigens. The macrophages did not possess C3 surface receptors.