Maria Angela Bianconcini Trindade

Increased Expression of Regulatory T Cells and Down-Regulatory Molecules in Lepromatous Leprosy

T regulatory cells (Tregs) play an important role in the mechanism of hosts failure to control pathogen dissemination in severe forms of different chronic granulomatous diseases, but their role in leprosy has not yet been elucidated; 28 newly diagnosed patients (16 patients with lepromatous leprosy and 12 patients with tuberculoid leprosy) and 6 healthy Mycobacterium leprae-exposed individuals (contacts) were studied. Tregs were quantified by flow cytometry (CD4+ CD25+ Foxp3+) in peripheral blood mononuclear cells stimulated in vitro with a M. leprae antigenic preparation and phytohemagglutinin as well as in skin lesions by immunohistochemistry. The lymphoproliferative (LPR), interleukin-10 (IL-10), and interferon-γ (IFN-γ) responses of the in vitro-stimulated peripheral blood mononuclear cells and the in situ expression of IL-10, transforming growth factor-β (TGF-β), and cytotoxic T-lymphocyte antigen 4 (CTLA-4) were also determined. We show that M. leprae antigens induced significantly lower LPR but significantly higher Treg numbers in lepromatous than tuberculoid patients and contacts. Mitogen-induced LPR and Treg frequencies were not significantly different among the three groups. Tregs were also more frequent in situ in lepromatous patients, and this finding was paralleled by increased expression of the antiinflammatory molecules IL-10 and CTLA-4 but not TGF-β. In lepromatous patients, Tregs were intermingled with vacuolized hystiocyte infiltrates all over the lesion, whereas in tuberculoid patients, Tregs were rare. Our results suggest that Tregs are present in increased numbers, and they may have a pathogenic role in leprosy patients harboring uncontrolled bacillary multiplication but not in those individuals capable of limiting M. leprae growth.

Granulomatous Reactivation during the Course of a Leprosy Infection: Reaction or Relapse

Background Leprosy is a chronic granulomatous infectious disease and is still endemic in many parts of the world. It causes disabilities which are the consequence of nerve damage. This damage is in most cases the result of immunological reactions. Objectives To investigate the differences between a type 1 leprosy (reversal) reaction and relapse on using histopathology. Methods The histopathological changes in 167 biopsies from 66 leprosy patients were studied. The patients were selected when their sequential biopsies demonstrated either different patterns or maintained the same pattern of granulomatous reaction over more than two years during or after the treatment of leprosy. Results In 57 of the patients studied, a reactivation was seen which coincided with a decrease in the bacteriological index (BI), suggesting that this reactivation (reversal reaction or type 1 leprosy reaction) coincides with an effective capacity for bacteriological clearance. In nine patients, an increase of the bacteriologic index (IB) or persistence of solid bacilli occurred during the reactivation, indicating proliferative activity, suggestive of a relapse. The histopathological aspects of the granulomas were similar in both groups. Conclusion Bacterioscopy provided the only means to differentiate a reversal reaction from a relapse in patients with granulomatous reactivation. The type 1 leprosy reaction may be considered as a part effective immune reconstitution (reversal, upgrading reaction) or as a mere hypersensitivity reaction (downgrading reaction) in a relapse.

Concomitant Lucio Phenomenon and Erythema Nodosum in a Leprosy Patient: Clues for Their Distinct Pathogeneses

Lepromatous leprosy patients may develop necrotic lesions, usually in the context of Lucio phenomenon (LP) or severe erythema nodosum (EN). The clinical and histopathological characteristics of the necrotic manifestations of both entities may eventually be confounded. We describe a patient with lepromatous leprosy who developed, since the 4th month of her first pregnancy, recurrent necrotic lesions in lower limbs, which, at the postpartum, worsened and led to partial destruction of ears and nose. In addition, she referred painful nodes on upper limbs since 1 year before pregnancy and intermittent swelling and tenderness of the ankles, which together with a right tibial and ulnar neuritis led to the diagnosis of, erythema nodosum leprosum (ENL). The histopathology of a biopsy of the upper limb (ENL) revealed a dermal-hypodermal inflammation with vasculitis and vascular lumen narrowing, whereas biopsy of the lower limb (LP) revealed small vessels with fibrin thrombi on the superficial layer of the dermis without inflammatory infiltrate and no evidence of vasculitis. Thus, besides having several different clinical features, LP and ENL result from different pathogenetic mechanisms. The histopathological and clinical features distinguishing both entities are proposed. This distinction is important because decrease in bacillary load through multidrug therapy is the main target in LP, whereas in ENL, concomitant reduction of the reaction by means of thalidomide or high-dose steroids is recommended.

Delayed diagnosis of multibacillary leprosy: a report of eight cases

Leprosy is an important public health problem in Brazil. However, this disease is still poorly diagnosed in its early stages, leading to permanent disability and disfigurement. We examined eight patients with clinical and histological diagnosis of multibacillary leprosy who were being treated for other diseases for about three years without clinical hypothesis of leprosy. These cases illustrate the importance of medical education and public information about leprosys signs and symptoms for prompt recognition and treatment, which are necessary to prevent permanent disabilities and eradicate the disease.

Histoid leprosy: clinical and histopathological analysis of patients in follow-up in University Clinical Hospital of endemic country

Histoid leprosy (HL) is a rare form of lepromatous leprosy, characterized by hyperchromic indurated nodules above normal skin. Its main histopathological aspect is spindle cells. Because it may simulate other aspects, such as dermatofibroma and neurofibroma, histoid leprosy poses itself as a diagnostic challenge.

A case report of erythroderma in a patient with borderline leprosy on reversal reaction: a result of the exacerbated reaction?

BackgroundErythroderma is characterized by erythema and scaling affecting more than 90% of the body surface area. Inflammatory, neoplastic and, more rarely, infectious diseases may culminate with erythroderma. Diagnosis of the underlying disorder is therefore crucial to institute the appropriate therapy. Leprosy is a chronic infectious disease that is endemic in Brazil. Here we present an unusual case of leprosy and reversal reaction causing erythroderma, and we discuss the underlying immunological mechanisms which could contribute to the generalized skin inflammation.Case presentationWe report a case of a patient with reversal reaction (RR) in borderline borderline leprosy presenting with erythroderma and neural disabilities. Histopathology of the skin showed regular acanthosis and spongiosis in the epidermis and, in the dermis, compact epithelioid granulomas as well as grouped and isolated bacilli. This duality probably reflects the transition from an anergic/multibacillary state to a state of more effective immunity and bacillary control, typical of RR. Leprosy was successfully treated with WHO’s multidrug therapy, plus prednisone for controlling the RR; the erythroderma resolved in parallel with this treatment. Immunologic studies showed in situ predominance of IFNγ + over IL-4+ lymphocytes and of IL-17+ over Foxp3+ lymphocytes, suggesting an exacerbated Th-1/Th-17 immunoreactivity and poor Th-2 and regulatory T-cell responses. Circulating Tregs were also diminished. We hypothesize that the flare-up of anti-mycobacteria immunoreactivity that underlies RR may have triggered the intense inflammatory skin lesions that culminated with erythroderma.ConclusionsThis case report highlights the importance of thorough clinical examination of erythrodermic patients in search for its etiology and suggests that an intense and probably uncontrolled leprosy RR can culminate in the development of erythroderma.