Neurophysiological patterns of ulnar nerve neuropathy in leprosy reactions

BACKGROUND

Leprosy neuropathy, despite being primarily demyelinating, frequently leads to axonal loss. Neurophysiological examination of the nerves during Type 1 (T1R) and Type 2 reactions (T2R) may give some insight into the pathophysiological mechanisms.

METHODS

Neurophysiological examinations were performed in 28 ulnar nerves during a clinical trial of steroid treatment effectiveness, 19 patients with T1R and nine with T2R. The nerves were monitored during a period of 6 months; there were eight assessments per nerve, for a total of 224 assessments. Nine neurophysiological parameters were assessed at three sites of the ulnar nerve. The compound motor action potential amplitudes elicited at wrist, elbow and above, as well as the conduction velocity and temporal dispersion across the elbow, were chosen to focus on the changes occurring in the parameters at the elbow tunnel.

RESULTS AND CONCLUSION

Neurophysiological changes indicating axonal and demyelinating processes during both T1R and T2R were detected across the elbow. Changes in demyelination, i.e. a Conduction Block, as a primary event present during T2R, occurring as an acute phenomenon, were observed regularly; in T1R Temporal Dispersion, a subacute phenomenon, was seen. During treatment remyelination occurred after both types of reactions.

Hansen's disease in a general hospital: uncommon presentations and delay in diagnosis

BACKGROUND

The question was raised as to why 'obvious' signs of leprosy, Hansen's disease (HD), are often missed by medical doctors working in a HD endemic area.

METHODS

This study describes a small sample of patients who were diagnosed with HD during their hospital admission and not before. The discussion is whether the typical early signs and symptoms of HD are just not recognized, or whether unusual presentations confuse the attending physician.

RESULTS

A total of 23 HD patients were hospitalized during the study period, of which 6 (26%) were only diagnosed with HD during their admission. All were classified as lepromatous leprosy (LL) with a history of signs and symptoms of HD. In nearly all patients, a suspicion of HD might have been raised earlier if a careful history and dermato-neurological examination had been done.

CONCLUSIONS

Multibacillary (MB) HD, especially close to the lepromatous end of the spectrum, may mimic other diseases, and the patient can not be diagnosed without a biopsy or a slit skin smear examination. Clinicians working in a HD endemic area (Rio de Janeiro) do not always include HD in their differential diagnosis, especially when the clinical presentation is unusual. HD should be considered in all patients with skin lesions not responding to treatment, especially when they have neurological deficits, and live or have lived in an HD endemic area. Due to the increase in global travel and immigration, doctors in low endemic areas need to consider HD as a possible diagnosis.

Two patients coinfected with Mycobacterium leprae and human immunodeficiency virus type 1 and naive for antiretroviral therapy who exhibited type 1 leprosy reactions mimicking the immune reconstitution inflammatory syndrome

Two case reports of patients with human immunodeficiency virus type 1 (HIV-1) infection who developed leprosy are presented. Both developed type 1 leprosy reactions in the absence of antiretroviral therapy. Reactions have been described for a number of HIV-1- and Mycobacterium leprae-coinfected patients and have been considered to be part of an immune reconstitution inflammatory syndrome (IRIS) since the reactions were usually linked to the administration of highly active antiretroviral therapy. The reports of our two patients suggest that the type 1 reactions in patients with leprosy and HIV may not always be an IRIS manifestation but may be akin to the classical reactional state described for the natural course of leprosy infection, which occurs in leprosy patients due to the fluctuations of the antimycobacterial immune response, whether they are coinfected with HIV or not.

Immunological crossreactivity of the Mycobacterium leprae CFP-10 with its homologue in Mycobacterium tuberculosis

Mycobacterium tuberculosis culture filtrate protein-10 (CFP-10) (Rv3874) is considered a promising antigen for the immunodiagnosis of tuberculosis (TB) together with early secreted antigens of M. tuberculosis (ESAT-6). Both ESAT-6 and CFP-10 are encoded by the RD1 region that is deleted from all tested M. bovis bacille Calmette-Guérin (BCG) strains but present in M. leprae, M. tuberculosis, M. bovis, M. kansasii, M. africanum and M. marinum. In this study, the homologue of CFP-10 in M. leprae (ML0050) is identified and characterized. Interferon-gamma production in response to this homologue by T cells from leprosy patients, TB patients and unexposed controls shows that CFP-10 of M. leprae is a potent antigen that crossreacts with CFP-10 of M. tuberculosis at the T-cell level. This crossreactivity has implications for the use of CFP-10 of these mycobacterial species as diagnostic tool in areas endemic for both the diseases.

Factors influencing the development of leprosy: an overview

The clinical manifestations of leprosy vary, seemingly depending on the host's immune response. Mode and route of infection, such as skin versus nasal mucosa, insect bites, sexual and gastroenteral transmission, together with genetic factors that may contribute to the outcome of the infection, including HLA, Lewis factor, Nramp1 and more subtle inherited alterations, are discussed. It is theorized that a balance between host responses elicited by different routes of infection and size and spacing of inocula is responsible for the clinical and immunological manifestations of the disease. Genetic factors and contact with environmental microorganisms may modulate these responses. The final result, resistance, delayed-type hypersensitivity, tolerance, disease or no disease, spectrum and reactions, is most likely reached via the orchestration of the induced cyto- and chemokines.

HLA-class II-associated control of antigen recognition by T cells in leprosy: a prominent role for the 30/31-kDa antigens

The recognition of 16 mycobacterial Ags by a panel of T cell lines from leprosy patients and healthy exposed individuals from an endemic population was examined within the context of expressed HLA-DR molecules. Although overall no significant differences were found between the frequencies of Ag recognition in the different subject groups, when Ag-specific T cell responses were examined within the context of HLA-DR, a highly significant difference was found in the recognition of the 30/31-kDa Ag. HLA-DR3 appeared to be associated with high T cell responsiveness to the 30/31-kDa Ag in healthy contacts (p = 0.01), but, conversely, with low T cell responsiveness to this Ag in tuberculoid patients (p = 0.005). Within the group of HLA-DR3-positive individuals, differences in 30/31-kDa directed T cell responsiveness were highly significant not only between healthy individuals and tuberculoid patients (p < 0. 0001), but also between healthy individuals and lepromatous patients (p = 0.009), and consequently between healthy individuals compared with leprosy patients as a group (p < 0.0001). A dominant HLA-DR3-restricted epitope was recognized by healthy contacts in this population. It has been proposed that secreted Ags may dominate acquired immunity early in infection. The low T cell response to the secreted, immunodominant 30/31-kDa Ag in HLA-DR3-positive leprosy patients in this population may result in retarded macrophage activation and delayed bacillary clearance, which in turn may lead to enhanced Ag load followed by T cell-mediated immunopathology.

The nose in leprosy: immunohistology of the nasal mucosa

A detailed study of the nose was undertaken in 40 leprosy patients with different classifications of leprosy and different durations of disease at two hospitals in Brazil. This manuscript describes the immunohistochemical data on cellular infiltrates in the nasal biopsies of those patients. It was surprising that the damage to the whole depth of the nasal mucosa, epithelium and lamina propria was considerable, as was the case in the nasal mucosa which looked relatively normal during clinical inspection. The epithelium showed large holes which looked like very extended goblet cells. Very obvious was the lack of vasoconstriction after cocaine application, and the vessels also showed a lack of staining with factor VIII, possibly indicating a disruption of the endothelium. The number of neurofilaments was extensively reduced in all leprosy groups compared to normal controls. As in the skin, an increased number of CD68+ cells was found in the lamina propria of the nasal mucosa of the lepromatous patients. Contrary to findings in the skin, in the nasal mucosa of the borderline/lepromatous patients the number of CD4+ cells was increased and the number of CD8+ cells was decreased compared to normal controls. The number of CD8+ cells tended to be more reduced when the history of leprosy was longer. It is not clear as yet whether the reduced numbers of CD8+ cells are acquired during infection or whether persons with a low number of CD8+ cells in the nose might have a higher risk of acquiring leprosy.

IL-2 and IL-12 act in synergy to overcome antigen-specific T cell unresponsiveness in mycobacterial disease

IL-12 secretion by APC is critical for the development of protective Th1-type responses in mycobacterial (Mycobacterium avium and Mycobacterium tuberculosis) infections in mice. We have studied the role of IL-12 and IL-2 in the generation of Mycobacterium leprae-specific T cell responses in humans. Leprosy patients were defined as low/nonresponders or high responders based on the level of T cell proliferation in M. leprae-stimulated PBMC. In high responders, M. leprae-induced proliferation was markedly suppressed by neutralizing anti-IL-12 mAb (inhibition 55 +/- 6%). Neutralization of IL-2 activity resulted in an inhibition of 77 +/- 4%. Given the importance of endogenous IL-2 and IL-12 in M. leprae-induced responses, we investigated the ability of rIL-2 and rIL-12 to reverse T cell unresponsiveness in low/nonresponder patients. Interestingly, rIL-12 and rIL-2 strongly synergized in restoring both M. leprae-specific T cell proliferation and IFN-gamma secretion almost completely to the level of responder patients. A similar synergy between rIL-2 and rIL-12 was also observed in high responders when suboptimal M. leprae concentrations were used for T cell stimulation. Our data demonstrate a crucial role for endogenous IL-12 and IL-2 in M. leprae-induced T cell activation. Most importantly, we show that rIL-2 and rIL-12 act in synergy to overcome Ag-specific Th1 cell unresponsiveness. These findings may be applicable to the design of antimicrobial and antitumor vaccines.

IL-2 and IL-12 act in synergy to overcome antigen-specific T cell unresponsiveness in mycobacterial disease

IL-12 secretion by APC is critical for the development of protective Th1-type responses in mycobacterial (Mycobacterium avium and Mycobacterium tuberculosis) infections in mice. We have studied the role of IL-12 and IL-2 in the generation of Mycobacterium leprae-specific T cell responses in humans. Leprosy patients were defined as low/nonresponders or high responders based on the level of T cell proliferation in M. leprae-stimulated PBMC. In high responders, M. leprae-induced proliferation was markedly suppressed by neutralizing anti-IL-12 mAb (inhibition 55 +/- 6%). Neutralization of IL-2 activity resulted in an inhibition of 77 +/- 4%. Given the importance of endogenous IL-2 and IL-12 in M. leprae-induced responses, we investigated the ability of rIL-2 and rIL-12 to reverse T cell unresponsiveness in low/nonresponder patients. Interestingly, rIL-12 and rIL-2 strongly synergized in restoring both M. leprae-specific T cell proliferation and IFN-gamma secretion almost completely to the level of responder patients. A similar synergy between rIL-2 and rIL-12 was also observed in high responders when suboptimal M. leprae concentrations were used for T cell stimulation. Our data demonstrate a crucial role for endogenous IL-12 and IL-2 in M. leprae-induced T cell activation. Most importantly, we show that rIL-2 and rIL-12 act in synergy to overcome Ag-specific Th1 cell unresponsiveness. These findings may be applicable to the design of antimicrobial and antitumor vaccines.

Molecular characterization and T-cell-stimulatory capacity of Mycobacterium leprae antigen T5

A Mycobacterium leprae lambda gt11 clone designated T5 has previously been selected with sera from tuberculoid leprosy patients. Sequence analysis of this clone revealed the presence of two overlapping open reading frames (ORFs) present on the two cDNA strands. The first ORF codes for the serologically recognized antigen, which was fused with the lacZ gene in the lambda gt11 clone. The second ORF, present on the complementary strand, displays strong sequence homology with the aspartyl-tRNA synthetase genes of Escherichia coli and Thermus thermophilus. Here we show that the purified T5-derived product, overexpressed in E. coli, is recognized by T cells of the majority of the leprosy patients tested, including lepromatous leprosy patients who do not respond to whole M. leprae bacilli.

[Leprosy in The Netherlands in the period 1970-1991]

OBJECTIVE

To inventory the changes in leprosy epidemiology in the Netherlands.

DESIGN

Retrospective.

SETTING

Academic Medical Centre (Amsterdam) and University Hospital Dijkzigt (Rotterdam), the Netherlands.

METHOD

The medical records of all new leprosy patients in the period 1970-1991 were analysed.

RESULTS

Between 1970 and 1991, 622 new leprosy patients were registered; 371 men (59.6%) and 251 women (40.4%). Most patients came from Surinam (73.3%) and Indonesia (7.2%). The mean time lapse between onset and treatment in the Netherlands was 10.1 years. Switching from monotherapy to combination therapy (1979) had no effect on the incidence of reversal reactions (cellular hypersensitivity in immunologically unstable patients), but did affect the incidence of erythema nodosum leprosum during the treatment.

CONCLUSION

Leprosy in the Netherlands is an important disease, mainly from Surinam. The main advantage of combination therapy is the shortened duration of treatment. The treatment of choice is the one recommended by the WHO, the combination therapy with rifampicin administration once a month, because of the few adverse effects.

Morphoea lesions are associated with aberrant expression of membrane cofactor protein and decay accelerating factor in vascular endothelium

One of the main features of systemic and localized forms of scleroderma is vascular damage, the mechanism of which is not yet understood. Recently, we have shown undetectable or decreased expression of complement regulatory molecules, membrane cofactor protein (MCP) and decay-accelerating factor (DAF), in cutaneous endothelium of patients with systemic sclerosis (SSc). In some patients, CD59 expression in endothelium was also altered. As these molecules protect endothelial cells from damage by autologous complement, their decreased expression could be part of the mechanism of vascular damage in SSc. In the present study, we investigated the expression of MCP, DAF and CD59 in the endothelium of lesional and non-lesional skin of patients with localized morphoea. Normal skin and lesional skin from patients with systemic lupus erythematosus, and three inflammatory diseases, were included as relevant controls. The results showed that the extent of expression of the three molecules in non-lesional skin of patients with morphoea, on all the skin cells and structures, was identical to that of normal skin. In lesional skin, however, the expression of MCP and DAF in endothelium was either undetectable or only present to a very slight degree. CD59 expression in endothelium in lesional skin was normal. No such aberrant expression was observed in the lesions of any of the control diseases. These results indicate a decreased ability of endothelial cells in lesional areas to protect themselves from autologous complement, and this could contribute to vascular damage in morphoea lesions.

Cosmetic tattooing as a treatment of port-wine stains

BACKGROUND

Medical treatment for port-wine stains frequently is cosmetically unsatisfactory. An alternative possibility is cosmetic medical tattooing.

METHODS

By means of a traditional Japanese tattooing technique, five patients were treated in multiple sessions until the color of the lesion matched that of the surrounding skin.

RESULTS

The results were excellent, the skin texture remained normal, and the patients could discontinue cosmetic camouflage.

DISCUSSIONS

Cosmetic medical tattooing when carefully done is a valuable addition to the medical armamentarium and may replace more aggressive techniques.

Diagnostic problems with imported cases of mycetoma in The Netherlands

Eight cases of imported mycetomata in The Netherlands are reviewed. Seven of these were cultured; only one isolate, Actinomadura madurae, belonged to a species commonly known as an agent of mycetoma. The remaining strains either belonged to very rare species, such as Phialophora cyanescens, or could not be identified at all. The list of possible agents of mycetoma apparently needs to be expanded. In addition, the concept of endemic occurrence of aetiological agents of eumycetoma needs revision. Divergent saprophytes may be involved which are able to survive in human tissue.

Similarity between mycobacterial and human epidermal antigens

Eight out of 17 mouse anti-Mycobacterium leprae monoclonal antibodies (MAb) were previously observed to react with human nerve and skin antigenic determinants in cryostat sections, using an indirect immunoperoxidase technique. These observations suggested that antigenic mimicry may be involved in the development of the clinical manifestations of leprosy. In the present study we have extended our earlier findings by investigating sera from leprosy patients and MAb using Western blot technique. It was observed that 30 sera and their corresponding F(ab')2 fragments from isolated IgG fractions of both tuberculoid and lepromatous patients reacted with 40-50 epidermal proteins of molecular weights (MW) ranging from 10 to 130 kDa. Sera from 14 controls, however, showed similar reactivity patterns. Absorption of nine patient and control sera with M. tuberculosis, M. marinum and M. kansasii resulted in the removal of several components of different MW in nine, four and three cases, respectively. No consistent differences between sera from leprosy patients and controls were observed. Four out of eight MAb against M. leprae which reacted with determinants in human epidermis and/or dermis in skin cryostat sections reacted with epidermal proteins of MW higher than 39 kDa in Western blot. Four MAb which showed reactivity in cryostat sections did not react in Western blot. Another four MAb did react with human epidermal proteins in Western blot but did not react in cryostat sections, indicating that the MAb were reacting with different epitopes in the two systems. Five MAb did not react with human epidermal proteins either in cryostat sections or in Western blot.(ABSTRACT TRUNCATED AT 250 WORDS)

Follow-up of multibacillary leprosy patients using a phenolic glycolipid-I-based ELISA. Do increasing ELISA-values after discontinuation of treatment indicate relapse?

With the introduction of reproducible serological tests it was hoped that relapses in leprosy patients, after discontinuing treatment, could be detected before damaging reactions occurred and before the patients became infectious. The possible value of an ELISA using a semisynthetic analogue of phenolic glycolipid-I to detect antibodies to this antigen in order to predict a relapse in multibacillary patients was investigated. In contrast to that reported for paucibacillary patients, this test was useful to detect early relapses in multibacillary patients. In 3 out of 4 multibacillary patients who relapsed, the ELISA-values were increased. The decreased ELISA-values in the one relapsed patient could be attributed to the corticosteroid therapy. In the multibacillary patients who did not relapse after RFT, the ELISA-values were consistently low or decreased. In only one patient did the ELISA-values increase following his release from treatment and this patient was clinically suspected of developing a relapse.

Bullous pemphigoid in children. Report of three cases with special emphasis on therapy

Three children aged 4 months, 7 years, and 12 years, had bullous pemphigoid (BP). Two children suffered from disseminated BP and one (12 years) from vulvar localized BP. This last form has been described only once before in a girl. The various forms of pemphigoid in childhood are rare and reported in only about 40 instances. Bullous pemphigoid in childhood does not differ clearly from the adult counterpart, although lesions of the mucous membranes seem more common in childhood.

Anti-Mycobacterium leprae monoclonal antibodies cross-react with human skin: an alternative explanation for the immune responses in leprosy

A panel of 17 mouse monoclonal antibodies (MoAb) raised against Mycobacterium leprae (M. leprae) antigens was used to detect antigenic determinants in normal human skin. An indirect immunoperoxidase technique was used. Eight of the MoAb detected epidermal antigens similar to patterns well known for human sera. Five of these MoAb detected determinants in the dermis, too. These observations may indicate a certain degree of similarity between the antigenic determinants occurring in M. leprae and in the human host. We propose that such a similarity on the one hand may facilitate the survival of M. leprae in the human host when the antigens are not recognized as "non-self," a situation which seems to occur in lepromatous leprosy, when the patients' tissues are loaded with bacteria virtually without any immune response. On the other hand, M. leprae antigens which mimic host antigens may induce an auto-immune reaction against the host's own antigens, which could explain the immune reaction in tuberculoid leprosy and during a "reversal reaction" when M. leprae is not observed in the host tissues, but extensive granuloma formation occurs.

Purpuric contact dermatitis to benzoyl peroxide

Patch test reactions in a patient with purpuric contact dermatitis to 5% benzoyl peroxide are described. Alterations of the capillary endothelium included obliteration of the lumina with perivascular mononuclear cell infiltrates. There were no epidermal alterations. These observations are discussed with reference to the data in the literature on vascular damage in "dermal" contact dermatitis.

Intralesional treatment of basal cell carcinoma with low-dose recombinant interferon gamma

In this pilot clinical trail the efficacy of intralesional low-dose human recombinant interferon-gamma was investigated in seven outpatients with nodular basal cell carcinoma. There was no antitumor response in any case. Toxic side effects were minimal. All tumors were excised surgically 8 weeks after completion of therapy.