Activation of complement by Mycobacterium leprae requires disruption of the bacilli

OBJECTIVE

The immune-mediated events that precipitate erythema nodosum leprosum (ENL) are not well understood. One component may be the complexing of antibody with antigens released from infected macrophages, the activation of complement and the subsequent local inflammation. We assess here the ability of highly-purified, disrupted M. leprae, to activate complement.

RESULTS

Intact and sonically-disrupted crude and alkali-purified nu/nu mouse-derived M. leprae suspensions were incubated with normal serum and a hemolytic titer (CH50) was determined as a measure of complement fixation. Crude M. leprae consumed complement, and disrupted preparations more than the intact. Purified M. leprae preparations did not consume complement unless disrupted.

CONCLUSION

M. leprae, if disrupted, can activate complement. This supports a hypothesis that links released antigens with ENL, and may explain the increased probability of an occurrence of ENL following chemotherapy.

Erythema nodosum and glatiramer acetate treatment in relapsing-remitting multiple sclerosis

Glatiramer acetate (GA), a well tolerated immunomodulatory treatment for relapsing—remitting multiple sclerosis (RR-MS), consists of a 4-amino acid polymer that mimics the myelin basic protein (MBP). We report the first case of biopsy-proven erythema nodosum (EN) in a patient presenting RR-MS under GA treatment. Comprehensive exams were negative in the search of the etiology of EN, which spontaneously resolved despite treatment continuation. GA treatment is known to generate reactive polyclonal antibodies that can cross-react with myelin epitopes, like MBP. These antibodies may also be implicated in allergenic reactions and auto-immune adverse events, such as anaphylactic shock, lymphadenopathy, livedo-like dermatitis, or lymphocytic infiltration. EN is an unspecific skin reaction occurring in several disorders and induced by many treatments. As EN can result from a polyclonal antibody response or type I hypersensitivity mechanisms, we hypothesize that GA treatment could be responsible for the occurrence of EN. Multiple Sclerosis 2007; 13: 941—944. http://msj.sagepub.com

Etanercept treatment of erythema nodosum

A 22-year-old otherwise healthy woman presented to the Vanderbilt University Dermatology Clinics with a 5-year history of painful, red plaques and nodules on her shins and tops of her feet. She had initially been seen by a rheumatologist, who diagnosed her with erythema nodosum (EN) and prescribed oral prednisone. After 1 month of therapy, the condition had not improved and she discontinued the treatment. She had undertaken no additional therapy in the interim. At the onset of her condition, she was taking no medications, using only etonogestrel/ethinyl estradiol vaginal ring for contraception. Her condition did not change after beginning this hormonal contraception. Her lesions were constant, with variable waxing and waning and without any discernible precipitants. They were tender to palpation but were otherwise without symptoms. She denied any history of fever, joint pain, fatigue, cough, gastrointestinal symptoms, malaise, mucosal ulcerations, foreign travel, infectious exposures, or illicit drug use. Clinically, her anterior legs displayed moderately well demarcated patches and nodules with dusky erythema. The lesions were tender to palpation but were not present on the feet or above the knees. Darkened, bruise-like areas were also appreciated and corresponded to older, quiescent lesions. Results from a chest x-ray, complete blood cell count, and metabolic panel were normal. She declined a biopsy. She was treated with supersaturated solution of potassium iodide, indomethacin, methotrexate, and dapsone, all without benefit. She was then begun on etanercept 25 mg administered subcutaneously twice weekly. After 1 month she noticed the lesions beginning to fade with a concomitant decrease in their discomfort, and by 4 months she was clear of her disease. Results of all monitoring blood work were normal. At 6 months, her disease had resolved and her etanercept dose was reduced by half without any flare of her condition. She has continued 25 mg weekly for 12 months without developing any new lesions.

Enhanced anti-mycobacterial immunity in children with erythema nodosum and a positive tuberculin skin test

Erythema nodosum (EN) may follow a variety of infections, but in regions with a high prevalence of tuberculosis, is frequently associated with a positive tuberculin skin test (TST) and tuberculosis infection. We aimed to investigate the immunological differences between patients with EN as a manifestation of primary tuberculosis, and those with progressive pulmonary tuberculosis (PTB) or asymptomatic infection. We studied the inflammatory response to both mycobacterial and non-mycobacterial antigens in 11 children with EN associated with a positive TST, 22 children with culture-confirmed tuberculosis, and 53 healthy skin test-positive children. In addition, we evaluated functional anti-mycobacterial immunity using an ex vivo assay of mycobacterial growth restriction in five children with EN and 15 with PTB. Patients with EN were distinguished by enhanced mycobacterial growth restriction on the functional assay, which was associated with a markedly increased production of IFNgamma in response to stimulation with purified protein derivative of Mycobacterium tuberculosis. Children presenting with EN and a positive TST show evidence of responses associated with enhanced anti-mycobacterial immunity.

Tumor necrosis factor receptors (TNFRs) on T lymphocytes and soluble TNFRs in different clinical courses of sarcoidosis

INTRODUCTION

The release of tumor necrosis factor (TNF-alpha) is increased in sarcoidosis patients. TNF-alpha exerts its effect by binding to specific cell surface receptors. There are only fragmentary data concerning the expression of tumor necrosis factor receptors (TNFRs) on bronchoalveolar lavage fluid (BALF) and peripheral blood (PB) lymphocytes. The aim of the study was to evaluate TNFRI (CD120a) and TNFRII (CD120b) expression on T cells and the level of soluble TNFRs in specimens of patients with different clinical manifestation and clinical outcome of sarcoidosis.

MATERIAL AND METHODS

We examined 49 patients with newly diagnosed pulmonary sarcoidosis. TNFRI and TNFRII density on CD4+ and CD8+ BALF and PB cells surface was estimated using monoclonal antibodies and a flow cytometry technique. The level of TNFRs in PB serum and BALF cell culture supernatant (CCS) was measured using ELISA. Immunological analyses were also performed on PB samples collected from 10 healthy volunteers.

RESULTS

The level of soluble TNFRI (sTNFRI) in PB serum was similar in sarcoidosis patients and healthy subjects, whereas the concentration of sTNFRII in serum was significantly higher in the sarcoidosis group (P<0.001). Patients without acute symptoms of sarcoidosis, patients with radiological stage II/III as well as patients with further disease progression showed a tendency to higher levels of sTNFRs in PB serum and lower levels of sTNFRs in BALF CCS compared to Löfgren syndrome and radiological stage I subjects, and patients with spontaneous resolution of sarcoidosis. More than 80% of BALF and PB lymphocytes of sarcoidosis patients expressed both CD120a and CD120b antigens. The percentage of double-positive CD4+CD120a+ and CD4+CD120b+ cells in PB was significantly higher (P<0.005) in sarcoidosis patients than in healthy subjects. The highest percentage of CD4+CD120a+ and CD4+CD120b+ lymphocytes in BALF was determined in patients with acute disease, and in PB of patients with further spontaneous improvement.

CONCLUSION

The evaluation of sTNFRs and TNFRs expression on T-helper cells may be useful in the estimation of sarcoidosis activity.

Effect of thalidomide on the expression of TNF-alpha m-RNA and synthesis of TNF-alpha in cells from leprosy patients with reversal reaction

Hypersensitivity reactions called reversal reaction (RR) and erythema nodosum leprosum (ENL) occur in leprosy. They are characterized by an increase in tumor necrosis factor-alpha (TNF-alpha). Thalidomide is an effective treatment for ENL but not RR. Its effectiveness in ENL is attributed to inhibition of TNF-alpha, and this does not explain its failure to treat RR. We assessed thalidomide's effect on TNF-alpha in RR. Mononuclear cells from RR and non-RR patients and healthy individuals were treated with thalidomide and M.leprae (AFB), a cytosol fraction of M. leprae or Dharmendra lepromin. Thalidomide suppressed TNF-alpha, but when some RR patients' cells were stimulated with AFB, it enhanced TNF-alpha.

Brucellosis with erythema nodosum-like manifestations diagnosed by isolated positivity of the ELISA test for anti-Brucella IgM

Brucellosis is endemic in the Mediterranean area. In spite of the false negative results, the standard agglutination test remains the routine test for the diagnosis of brucellosis in southern Italy. We present a case of a patient with undulant fever and erythema nodosum-like skin lesions, with negative serum agglutination test, but isolated positivity of the ELISA test for anti-Brucella IgM. A diagnosis of brucellosis for this patient was supported by the anamnestic and clinical data, and by the response to therapy. This case and a review of the literature urge us to consider the ELISA test indispensable for the serological diagnosis of brucellosis.

CTLA-4 gene 49A/G polymorphism in Turkish patients with Behçet's disease

Genetic factors predisposing individuals to Behçet's disease (BD) are considered to play important roles in the development of the disease. Patients with BD exhibit elevated levels of pro-inflammatory cytokines, and affected organs show a significant neutrophil and lymphocyte infiltration. Current evidence suggests that the activated lymphocytes contribute to neutrophil and endothelial cell activation in these patients. The cytotoxic T lymphocyte-associated antigen (CTLA)-4 molecule plays an important role in immune regulation by downregulating T-cell activation, and the CTLA-4 49A/G polymorphism in the exon 1 has been shown to be associated with a number of autoimmune diseases. In an attempt to demonstrate whether there is an association of the CTLA-4 49A/G polymorphism with BD in the Turkish population, we genotyped 59 Turkish patients and 99 healthy individuals for single-nucleotide polymorphisms. For this purpose, genomic DNA was obtained from the peripheral blood of individuals and the region of interest was amplified using PCR. Genotyping was performed using the BbvI restriction endonuclease. It was shown that the distribution of the CTLA-4 exon 1 49A/G allele and genotype frequencies did not differ between patients with BD and healthy controls. However, allele and genotype frequencies of CTLA-4 49 A and A/A were significantly higher in patients with ocular involvement compared with patients without these symptoms (90.6% vs. 65.1%, odds ratio (OR) = 9.67, P = 0.011; and 81.25% vs. 39.5%, OR = 9.56, P = 0.015, respectively). A statistically significant difference in the A allele frequency was observed in patients with erythema nodosum-like lesions (86.1% vs. 65.8%, OR = 6.24, P = 0.04). There was also an increase in A/A genotype frequency, but the difference was not statistically significant (72.2% vs. 41.5%, OR = 6.5, P = 0.068). Our data suggest that BD patients with ocular involvement and erythema nodosum-like lesions have a higher frequency of both the A allele and the A/A genotype at position 49 of exon 1 of CTLA-4. These results may also indicate that CTLA-4 is a disease-modifying rather than a susceptibility gene for BD.

Effective treatment of erythema nodosum leprosum with thalidomide is associated with immune stimulation

The immunomodulatory drug thalidomide is the treatment of choice for erythema nodosum leprosum (ENL), an inflammatory cutaneous and systemic complication of multibacillary leprosy. To elucidate the mechanism of action of thalidomide in this syndrome, we prospectively investigated 20 patients with ENL who were treated with thalidomide for 21 days. All patients responded to treatment, with the majority of them having complete resolution of cutaneous lesions within 7 days. This response was associated with a marked but transient increase in ex vivo mitogen-induced expression of interleukin (IL)-2 and interferon- gamma by CD4(+) and CD8(+) T cells that was observed on treatment day 7, but these returned to pretreatment levels by day 21. Plasma tumor necrosis factor- alpha levels were not high at baseline, and they increased modestly during treatment. Plasma levels of IL-12 increased steadily during thalidomide treatment. Hence, the therapeutic effect of thalidomide in ENL appears to be associated with transient immune stimulation, which suggests that the drug may promote an active immunoregulatory response.

Lucio's phenomenon/erythema necroticans

Lucio's phenomenon/erythema necroticans is a peculiar reaction pattern that occurs in untreated pure primitive diffuse lepromatous leprosy (PPDL) and/or relapsing leprosy recognized as spotted leprosy of Lucio. The small number of reported cases in the world literature suggests that it is fairly uncommon. Its clinical features are fairly characteristic and consist of extensive, bizarre, painful ulcerations of the skin, with constitutional symptoms being conspicuous by their absence. The clinical diagnosis is confirmed by microscopic pathology marked by proliferation and mobilization of polyblasts and histiocytes, dilatation, endothelial proliferation, luminal occlusion, and thrombosis of the superficial and mid-dermal blood vessels and demonstration of acid-fast bacilli in the blood vessel walls. Its precise pathogenesis is still unclear, but is believed to occur either through the usual or the alternate pathway of complement activation in the natural history of erythema nodosum leprosum. The clinical and immunological features of reactions in leprosy, including erythema nodosum leprosum, are well known and have been critically evaluated elsewhere.

High expression of myeloid-related proteins 8 and 14 characterizes an inflammatorily active but ineffective response of macrophages during leprosy

Macrophages are decisive cells for the course of leprosy as they phagocytose Mycobacterium leprae and have the potential to influence the specific immune response. Expression and release of the myeloid-related protein (MRP) 8 and MRP14 (S100A8 and S100A9) characterize a proinflammatory subtype of macrophage that is prominent in, for example, murine infection with lack of a T helper 1 cell response and in certain highly active chronic inflammations of mice and humans. We investigated cutaneous biopsies of the different forms of leprosy (41 untreated patients) including leprosy reaction type 1 (reversal reaction) and type 2 (erythema nodosum leprosum) (n = 18) for expression of MRP8 and MRP14 by subtypes of macrophages. Concomitantly we determined serum levels of MRP8 and MRP14 by sandwich enzyme-linked immunosorbent assay. Expression of MRP8 and MRP14 by CD68-positive macrophages was low in tuberculoid leprosy and rose significantly in borderline tuberculoid leprosy and especially in multibacillary forms, there being expressed by mycobacteria-loaded foam cells. A significant rise of MRP8 and MRP14 expression also occurred in lepra reactions compared to the corresponding non-reactional forms. In type 2 reactions this additional increase was associated with a significant elevation of serum levels. In type 1 it was associated with expression of MRP8 and MRP14 by epitheloid and giant cells, which so far were considered not to express both proteins. In conclusion, we present evidence that the two prominent proteins MRP8 and MRP14 can be re-expressed in vivo by tissue macrophages in chronic infection, that their increased expression is characteristic for a macrophage subtype associated with high inflammatory but low antimycobacterial activity in the absence of a T helper 1 response, and that their significant rise in serum during erythema nodosum leprosum bears diagnostic and pathophysiological relevance.

[Review: update on erythema nodosum leprosum]

Erythema nodosum leprosum (ENL) is an immunological reaction corresponding to vascularitis due to circulating immune complexes usually occurring during treatment of lepromatous leprosy. The precise mechanism underlying ENL are unclear but involvement of tumor necrosis factor alpha (TNFalpha) is suspected. Based on this suspicion pentoxifylline has been used instead of conventional treatments such as corticosteroids and thalidomide.

[Pentoxifylline in the treatment of erythema nodosum leprosum: results of an open study]

Erythema nodosum leprosum (ENL) is a well-known immunological serious complication affecting lepromatous multibacillary leprosy patients. For a long time, ENL has been regarded as an immune complex-mediated disease or Arthus phenomenon. Recently, it has been reported that ENL was associated with high serum tumor necrosis factor-alpha (TNFa) levels, suggesting that this cytokine could also play a central role in the manifestations of ENL. Thalidomide (TH) and systemic steroids (S), both TNFa production inhibitors, are the two current effective drugs for the management of ENL. However, TH is rarely available in leprosy endemic countries, and its teratogenicity and neurotoxicity strongly limit its use. Moreover, the morbidity of S and the frequent steroid-dependence of ENL also create real therapeutic problems. Recently, the efficacy of pentoxifylline (PTX), which also inhibits in vitro and in vivo production of TNFa, has been suggested for ENL treatment. We report our experience on its use for the treatment of 15 leprosy patients suffering from a first ENL. attack. (11 cases), a chronic steroid-dependent ENL (3 cases) or chronic steroid- and thalidomide-dependent ENL (1 case). PTX has been given at 800 mg t.i.d, (2 cases) or 400 mg t.i.d. (13 cases) doses. The patients received PTX at the initiating dosage until complete clinical cure. At the end of ENL attacks, PTX was either abruptly stopped or tapered down over the next 4 months. In ten of 11 patients who developed ENL for the first time, the systemic symptoms and neuritic pains disappeared within one week; at three weeks, half of the patients were cured and the other half had striking clinical improvement; complete cure was obtained within 7 to 35 days (mean: 27 days). A relapse occurred within 2-3 months in the 5 patients, in which PTX was abruptly stopped. In contrast, no relapse occurred in the patients who benefited from decreasing doses of PTX. Recurrent ENL episodes also responded well to PTX. The 3 patients who had chronic steroid-dependent ENL failed to show any improvement after 3 to 6 weeks of PTX. In contrast, steroid therapy could be stopped in the steroid- and thalidomide-dependent patient. Our results confirm the action of PTX if it is slowly tapered down (4 months seem sufficient) and not abruptly to avoid relapses. As it is safe use, PTX could constitute the first line of ENL attack treatment.

Pattern of bacillary clearance in multibacillary leprosy patients with multidrug therapy

The bacteriological index (BI) of the skin smears is traditionally one of the important parameters of assessment of severity and of progress of leprosy under multidrug therapy. The present study reports on BI clearance among 578 multibacillary treated leprosy patients and the factors that influence this clearance. The patients were treated till smear negativity or for 2 years fixed duration and their skin smears periodically examined every 6 to 12 months till negativity (and even afterwards). We confirm that bacterial clearance is a slow process. The time taken for each log-unit decline in BI is between 13.6 to 24 months probably depending on initial BI level. The rate of smear negativity appears to be dependent on immune competence of the patients as reflected by a rapid BI decline in borderline BT-BB patients vis-à-vis BL-LL lepromatous patients both in the low and high BI group. Patients who had several episodes of ENL, took significantly longer time (63.7 months versus 53.5 months, p<0.0001) to become smear negative than those without ENL.

Plasma activity of interleukin-10 in drug-induced cutaneous reactions

Plasma concentrations of interleukin-10 (IL-10) were examined in 126 patients with drug-induced cutaneous reactions: maculopapular eruptions (ME), erythema multiforme (EM), erythema multiforme coexisting with erythema nodosum (EMN), drug-induced urticaria (DU), hyperergic vasculitis (HV), Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN). Activity of the cytokine was measured using the immunoenzymatic ELISA method: a) in the acute stage of disease before treatment was administered, and b) after clearing of skin lesions, after treatment. In the acute stage of disease highly elevated mean concentrations of IL-10 in all 6 groups of patients were found (p<0.001) in comparison with the control. After clearing of clinical symptoms IL-10 concentrations were decreased highly significantly (ME, EM, DU, HV) or significantly (EMN, SJS/TEN) in comparison with the values before treatment, but remained still considerably elevated (p<0.001; p<0.01) when compared with the healthy control. Results of this study indicate that the compensatory antiinflammatory response, expressed as elevated IL-10 activity, is induced as early as in the acute stage of skin lesions and lasts longer than clinical symptoms of drug-induced cutaneous reactions.

Tinea barbae associated with erythema nodosum in an immunocompetent man

We describe the case of a 45-year-old man with atopy who developed marked inflammatory lesions on the bearded area of the face caused by Tricophyton rubrum, an anthropophilic fungus not frequently correlated with kerion of the face. After starting therapy with griseofulvin, he developed typical lesions of erythema nodosum on both legs. We discuss how these lesions could be correlated with the kerion of the face.

Erythema nodosum associated with antiphospholipid antibodies: a report of three cases

Erythema nodosum is a dermatologic condition characterized by painful, erythematous nodules on the anterior surfaces of the lower extremities. Its association with a variety of conditions has been previously described. We present three cases of erythema nodosum in patients with elevated anticardiolipin antibodies. In one patient, a temporal relationship was seen in the simultaneous detection of antibodies and skin lesions. We propose an association between erythema nodosum and the antiphospholipid antibody syndrome (APS).

Sequential erythema nodosum leprosum and reversal reaction with similar lesional cytokine mRNA patterns in a borderline leprosy patient

We compare the clinical and histological data with the immunological status of a borderline leprosy patient who experienced an erythema nodosum leprosum (ENL) reaction followed by a reversal reaction (RR) after 12 weeks of anti-inflammatory treatment (pentoxifylline, PTX, 1200 mg daily). Skin biopsies, serum and blood samples were collected sequentially during the reactional episodes. At the outset of RR, the patient's lymphocytes secreted interferon (IFN) -gamma and there was a positive lymphoproliferative test in response to Mycobacterium leprae, which had been absent during ENL. The lepromin reaction reversed from negative (0 mm) at diagnosis, to positive (3 mm) 3 months after the development of RR. Tumour necrosis factor (TNF) -alpha levels in the serum decreased after 1 week of treatment and increased slightly thereafter. The immunohistochemical data for ENL showed a diffuse dermal and hypodermal infiltrate composed of mononuclear cells and neutrophils, while RR was characterized by an epithelioid granulomatous infiltrate with a marked presence of gammadelta T cells. Reverse transcription-polymerase chain reaction showed a mixed cytokine profile characterized by the expression of TNF-alpha, IFN-gamma, interleukin (IL) -6, IL-10 and IL-12 mRNA in the skin, which persisted throughout the development of ENL and RR lesions. IL-4 mRNA, first detected after 7 days of PTX treatment, was still present during RR. The results suggest the emergence of an initial Th0-like cytokine profile in ENL, typical of a state of immunoactivation, before conditions optimal for the appearance of an antigen-specific cell-mediated immune response and gammadelta T-cell migration are created.