Clinical patterns of cutaneous nontuberculous mycobacterial infections.

BACKGROUND: Cutaneous nontuberculous mycobacterial infections result from external inoculation, spread of a deeper infection, or haematogenous spread of a disseminated infection. There are two species-specific infections (fish-tank or swimming-pool granuloma, due to Mycobacterium marinum, and Buruli ulcer, caused by M. ulcerans). Most infections, however, produce a nonspecific clinical picture. OBJECTIVES: To define clinical patterns of cutaneous disease in nontuberculous mycobacterial infections. METHODS: Fifty-one patients with cutaneous nontuberculous mycobacterial infections were reviewed. Clinical and histopathological features of normal hosts and immunosuppressed patients were compared. Two subgroups of immunosuppressed patients were distinguished: patients with cutaneous infection and patients with a disseminated infection and cutaneous involvement. RESULTS: In immunosuppressed patients the number of lesions was significantly higher. Abscesses and ulceration were also more frequently observed. Different species were found in normal hosts and immunosuppressed patients. Several clinical patterns of cutaneous infection were defined: lymphocutaneous or sporotrichoid lesions; nonlymphocutaneous lesions at the site of trauma; folliculitis and furunculosis involving the lower extremities; disseminated lesions on the extremities in immunosuppressed patients. Two patterns were observed in patients with a disseminated infection: localized cutaneous lesions and disseminated cutaneous and mucosal lesions. CONCLUSIONS: Cutaneous manifestations of nontuberculous mycobacterial infections may be classified according to criteria such as cutaneous lesions and immune status.

Cutaneous infections due to nontuberculous mycobacteria: histopathological review of 28 cases. Comparative study between lesions observed in immunosuppressed patients and normal hosts.

To evaluate the histopathological features observed in patients with cutaneous infections due to nontuberculous mycobacteria (NTM) and to compare the histopathological patterns observed in immunosuppressed patients and normal hosts. Twenty-eight biopsy specimens corresponding to 27 patients with cutaneous infections due to NTM were reviewed. Eighteen biopsies corresponded to normal hosts (14 Mycobacterium marinum, 2 Mycobacterium chelonae, 1 Mycobacterium terrae and 1 Mycobacterium gordonae) and 10 biopsy specimens were obtained from 9 immunosuppressed patients (3 Mycobacterium chelonae, one of which had two biopsies, 1 Mycobacterium abscessus, 2 Mycobacterium kansasii, 1 Mycobacterium marinum, 1 Mycobacterium avium complex and 1 Mycobacterium simiae). A panel of histopathological features was evaluated by two independent observers in each biopsy specimen. Epidermal changes (acanthosis, pseudoepitheliomatous hyperplasia, exocytosis) were mainly observed in M. marinum infections. In immunosuppressed patients the infiltrate tended to be deeper, involving the subcutaneous tissue (100%) with a more diffuse distribution and constant abscess formation. A marked granulomatous inflammatory reaction was observed in 83% of immunocompetent and in 60% of immunosuppressed patients. In immunosuppressed patients a relationship between the chronic evolution of the disease and granuloma formation was demonstrated. A diffuse infiltrate of histiocytes with occasionally foamy appearance was noted in three biopsy specimens from three patients with AIDS. Acute and chronic panniculitis was detected in 8 biopsy specimens. In one biopsy (M. chelonae) an acute suppurative folliculitis was observed. Different histopathological patterns can be noted in biopsy specimens from cutaneous nontuberculous mycobacterial infections. The evolution of the disease and the immunologic status of the host may explain this spectrum of morphological changes. Tuberculoid, palisading and sarcoid-like granulomas, a diffuse infiltrate of histiocytic foamy cells, acute and chronic panniculitis, non-specific chronic inflammation, cutaneous abscesses, suppurative granulomas and necrotizing folliculitis can be detected. Suppurative granulomas are the most characteristic feature in skin biopsy specimens from cutaneous NTM infections. Some histopathological patterns seem more prevalent in immunosuppressed patients.

Mycosis fungoides associated with unusual epidermal hyperplasia.

A 58-year-old white woman presented with widespread pruritic brownish plaques and hyperpigmented flexural lesions with a velvety appearance. On histopathological examination, the macules were diagnostic of mycosis fungoides, plaque stage, and the flexural lesions showed epidermal hyperplasia with a seborrhoeic keratosis-like appearance. There was intense mucin deposition and marked reduction of elastic fibres in the papillary dermis, as well as a moderately dense dermal lymphoid infiltrate composed of CD4+ T cells with occasional atypia and focal epidermotropism. The clinical and pathological manifestations of cutaneous T-cell lymphomas, including mycosis fungoides (MF), may show considerable variation. Apart from the three classic stages, a number of unusual clinical presentations and a broad spectrum of histopathological findings have been reported in the literature. In this report, a case of MF, plaque stage, with flexural lesions clinically reminiscent of (pseudo)acanthosis nigricans is presented. On histopathological examination, there was epidermal hyperplasia with a seborrhoeic keratosis-like appearance, with intense deposition of mucin and marked reduction of elastic fibres in the papillary dermis, together with a lymphoid infiltrate composed mainly of CD4+ cells with occasional atypia and epidermotropism. Cytokines produced by the lymphocytes in the infiltrate might account for the epithelial and dermal changes that characterize this peculiar variant of MF.

Systemic capillary leak syndrome.

Systemic capillary leak syndrome is a rare, severe disorder with a high mortality rate. It consists of the shift of fluid and proteins from the intravascular to the extravascular compartment with subsequent hypovolemic shock. We describe a 34-year-old-woman who had several episodes of generalized edema that evolved to hypovolemic shock. During the acute phase, laboratory investigations revealed marked hypoproteinemia, leukocytosis, and high levels of hematocrit and hemoglobin. A paraprotein IgG kappa chain was detected. Although different therapeutic trials were used, the patient continued to have similar episodes and she died during an acute episode 2 1/2 years after the first symptom of this disorder. The cause of systemic capillary leak syndrome is unknown. The presence of a paraprotein IgG is frequent in this group of patients.

Acute febrile neutrophilic dermatosis (Sweet's syndrome).

BACKGROUND: Sweet's syndrome is well recognized and not infrequently diagnosed in Spain; however, the range of clinical and pathologic expression may not have been fully realized. METHODS: We reviewed 30 consecutive Spanish cases of Sweet's syndrome diagnosed in our department from 1979 to 1990, with special attention to clinical and histopathologic findings. RESULTS: Distinctive clinical features in our series included oral mucosa lesions in four patients (13%), development of pathergy phenomenon in one case, concurrent nodular lesions resembling erythema nodosum on the limbs in nine cases (30%), and lung involvement in two patients. Infectious disease and drug treatment were recorded as possible triggering factors of Sweet's syndrome in eight and seven patients respectively. Associated underlying systemic disorders were present in 15 (50%) of our patients. The most frequent associations were hematologic neoplasia in four patients, solid neoplasia in two, and chronic idiopathic inflammatory bowel disease in three patients. Dressler's syndrome and sicca syndrome were found in one patient each. Histopathologic studies of skin biopsy specimens obtained at presentation disclosed typical features of Sweet's syndrome in all cases. Epidermal involvement, with variable degrees of spongiosis, exocytosis of polymorphonuclear leukocytes and keratinocyte necrosis, was a prominent feature in 83% of biopsy specimens. CONCLUSIONS: Further characterization of the clinicopathologic spectrum of Sweet's syndrome is necessary as the recognition of the full spectrum of this syndrome will improve our diagnostic abilities and provide a solid clinical basis for prospective studies that allow dissection of the intricate patho-mechanisms involved in this fascinating disorder.

Leukemic dermal infiltrate at the exit site of a central venous catheter.

This report describes the case of a minimally differentiated acute myeloid leukemia (FAB M0) diagnosed in a 55-year-old woman. During a second chemotherapy-induced complete remission, a subcutaneous nodule appeared at the scar of a recently removed Hickman catheter, which when biopsied revealed leukemic infiltration of the dermis and hypodermis. The patient had a bone marrow relapse three weeks later. The authors review similar recent reports and emphasize the importance of recognizing this particular type of cutaneous leukemic relapse.