Tropical and exotic dermatoses and ulcers

BACKGROUND

Tropical dermatoses and ulcers, although essentially unique to tropical and subtropical areas, are occasionally seen in Australian general practice on returning travellers and migrants from endemic countries.

OBJECTIVE

This article will discuss important causes of tropical and exotic ulcers occasionally seen in Australia.

DISCUSSION

As tropical ulcers may mimic many other causes of skin ulceration and nodules, a history of recent travel should arouse clinical suspicion. The time frame since exposure to the causative organism is an important feature in the diagnostic process. For example, pyodermas and cutaneous larva migrans present a few days after contact with the causative agents, whereas leishmaniasis, cutaneous tuberculosis, atypical mycobacterial diseases (swimming pool granulomas) and tropical mycosis take weeks to months to appear.

Scrofuloderma--a case series from rural India

Cutaneous tuberculosis is the rarest presentation of all the forms of tuberculosis. Scrofuloderma is a frequent manifestation of cutaneous tuberculosis in Indian scenario. Males are affected one and half times more than females. The most common affected age group showing clinical infection is within the first three decades of life. A series of cases mostly malnourished children attending a tertiary care centre in a rural area of central India is being reported. They have presented with a wide spectrum of clinical features, forcing us to establish the final diagnosis by Mantoux test, fine needle aspiration cytology and histopathological examination. The mainstay of treatment remains medical therapy but the underlying cause for severe immunosuppression needs to be ruled out and treated.

Cutaneous tuberculosis--a study of 400 cases

A prospective study was conducted on 400 cases having clinical manifestation of cutaneous tuberculosis from 1992 to 2001 in the department of Dermatology and Venereology, Dhaka Medical College Hospital (DMCH) and Bangabandhu Sheikh Mujib Medical University (BSMMU), formerly Institute of Postgraduate Medicine and Research, Dhaka, Bangladesh. The clinical diagnosis was confirmed by histopathological examination. Among 400 cases, 260 (65%) were males and 140 (35%) were females with a male to female ratio 1.86:1. Age ranged from 10 to 70 years. Majority of the cases 200 (50%) were diagnosed as Tuberculosis verucosa cuties, 160 cases (40%) and 40 cases (10%) were diagnosed as Lupus vulgaris and Scrofuloderma respectively. All patients received combined antitubercular therapy.

Severe disseminated tuberculosis in a 4-month-old infant initially presenting with multiform cutaneous lesions

A 4-month-old female infant presented with 1 month history of horizontal nystagmus and discrete multiform skin lesions. The patient was initially diagnosed with congenital nystagmus and staphylococcal skin infection not responding to antimicrobial agents. The development of severe systemic symptoms led to extensive investigations and the diagnosis of disseminated tuberculosis. Mycobacterium tuberculosis (MTB) was isolated from the skin and cerebrospinal fluid. The patient was treated with isoniazid, rifampicin, pyrizinamide, streptomycin and dexamethasone. Skin lesions resolved completely but severe neurological deficits persisted.

[Extrapulmonary tuberculosis: case of a 70-year-old woman suffering from cutaneous lymph node, renal and bone tuberculosis ]

We have described a case of a 70-year-old woman, treated for a pancreas cancer, which was diagnosed for many months because of atypical skin lesions, lymphadenopathy and progressing cachexia. Despite many autoimmunological, serological, histopathological, bacteriological and mycological examinations there was no diagnosis. Finally the case of extrapulmonary tuberculosis involving skin, lymph nodes, kidneys and bones was diagnosed. After the introduction of antituberculotic therapy we are observing some clinical improvement and regression of symptoms.

Fish tank exposure and cutaneous infections due to Mycobacterium marinum: tuberculin skin testing, treatment, and prevention

In the present study, 8 patients with soft tissue infection due to Mycobacterium marinum are described, and contemporary data on treatment are reviewed. Six patients had positive cultures, all patients had cutaneous exposure to fish tanks, 7 had sporotrichoid lesions, and 2 had deep infection. All 7 tested patients had tuberculin skin test reactions > or =10 mm. Six patients with disease limited to the skin were successfully treated with 2-drug combination therapy, including clarithromycin, ethambutol, and rifampin. Optimal treatment should include 2 drugs for 1-2 months after resolution of lesions, typically 3-4 months in total. Deeper infections may require more prolonged treatment and surgical debridement. Positive tuberculin reactions may be due to infection with M. marinum. Persons with open skin lesions or immunosuppression should avoid cutaneous contact with fish tanks.

Assessment of functional limitations caused by Mycobacterium ulcerans infection: towards a Buruli ulcer functional limitation score

The purpose of this study of treated Buruli ulcer patients in Ghana was to identify and assess late sequelae of treated Buruli ulcer using a goniometer, and to develop a scoring system for functional limitations. Of 78 patients, 58% (n = 45) had a reduction in the range of motion of one or more joints: 30% (n = 23) had one or more functional limitations of the leg and 21% (n = 16) of the arm; 49% (n = 38) had a functional limitation. Of all patients with affected knees, the predicted average extent of limitation was 63%. In patients with affected ankles, limitation was 78% on average; in those with elbow involvement, this was 76% on average, and in wrists involved, 65%. All of the hands involved were markedly restricted. We propose a simplified and functional scoring system that should be tested for validation in a second patient sample, and, if properly validated and adjusted, can be used in future intervention trials.

[Manifestations, diagnosis and treatment of non-tuberculous mycobacterial infections in non-immunodepressed patients]

Non-tuberculous mycobacteria (NTM) can be the etiologic agents of chronic pulmonary disease, lymphadenitis, skin and soft-tissue infection and disseminated disease in non-immunocompromised patients. The recognition of disease needs repeated isolation of the NTM from bronchopulmonary secretions or from tissue biopsies, and its identification by specific laboratory methods. A wide spectrum of clinical presentations and severity of disease can be found, from spontaneous healing to progressive and destructive lung disease, and death, according to predisposing conditions and mycobacterial species. The choice of surgical and drug treatment will depend on identification of specific pathogen and clinical evaluation.

Transepithelial elimination of granulomas in cutaneous tuberculosis and sarcoidosis

Transepithelial elimination of granulomas was observed in histologic specimens taken from involved skin of a patient with disseminated tuberculosis and two patients with sarcoidosis. This phenomenon, previously also observed in other granulomatous disorders, represents one of the skin's several mechanisms to rid itself of endogenous or exogenous waste material.