[Dermatological problems in visitors to the tropics]

Diseases of the skin are common in travellers returning from the tropics and immigrants from tropical countries, and often pose a challenge for physicians in the industrialized world. In addition to the cosmopolitan skin diseases, dermatoses linked specifically to the geoclimatic and socio-economic conditions prevailing in the tropics. To correctly diagnose such dermatological lesions, knowledge of the respective geographic aspects and tropical medicine is a must. An unusual climate and contact with microorganisms, parasites and insects not normally encountered can result in a specific spectrum of skin problems in persons who spend time in tropical regions.

[Yellow fever--a tropical danger]

Yellow fever is an acute life-threatening viral infection. In the case of the urban type, the virus is transmitted from one human to another by the Aedes mosquito vector. In particular travelers to Africa from non-endemic areas run a high risk of clinical disease in case of infection. For prophylaxis, a reliable live virus vaccine is available.

[Elephantiasis soon eliminated? New therapeutic concepts make mass treatment possible]

Lymphatic filariasis currently affects some 120 million people in 73 tropical countries. Almost one-half of all those affected have manifest signs and symptoms of disease, of which elephantiasis is the most serious. A large majority of the remainder have subclinical lymphopathy and nephropathy. New scientific discoveries give rise to the hope that the global elimination of this disease--which is associated with physical disfigurement, sexual dysfunction and social decline--might be possible. Today, we have available simple diagnostic tools and highly effective, safe and cost-effective medications. New insights into the pathogenesis now make it possible to alleviate individual suffering and prevent further progression of the disease.

[Psychosocial, economic and physical status of former leprosy patients in Uganda]

This study investigates the general living condition, the psychosocial, economical and physical situation of 161 leprosy patients previously treated at the St. Francis Leprosy Hospital at Buluba/Uganda, basing on interviews and clinical examinations. The results point to a negative correlation between general education and specific knowledge of leprosy and highlight a serious psychosocial situation of previously treated leprosy patients. The most important conclusion is that besides leprosy-specific chemotherapy, lifelong extensive general and leprosy-specific health education and posttreatment care can prevent disabilities in leprosy patients.

Onchocerciasis: clinical presentation and host parasite interactions in patients of southern Sudan

BACKGROUND

Onchocerciasis, an infection by the filarial nematode Onchoverca volvulus, is widely distributed in tropical Africa and of great dermatologic interest. This study analyses the dermatologic presentation and tries to determine the correlations between clinical disease and host parasite interactions in onchocerciasis patients of the Southern Sudan.

METHODS

We performed clinical and histopathologic investigations in patients with onchocerciasis in the Wau District, Bahr el Ghazal Province, Southern Sudan. As well as a detailed clinical skin examination, skin biopsies were taken, processed, and investigated for type and degree of host tissue response. Parasitologic, clinical, and histopathologic findings were evaluated.

RESULTS

Onchocerciasis appears with a variety of severe skin lesions. Central is a pruritic rash. Long-standing cases develop extensive pigmentary changes and impressive signs of skin tissue exhaustion. Cellular host tissue responses to degenerating skin microfilariae seem to play a key role in the development of skin pathology. The degree of host response appears to be inversely proportional to the host's microfilarial load.

CONCLUSIONS

Onchocerciasis represents a health problem of great dermatologic importance in Southern Sudan. The study results demonstrate clinical variations in onchocerciasis and provide support for the existence of a disease spectrum.

Ocular complications observed in leprosy patients in Romania

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[Leprosy in Africa. Current status and epidemiological significance]

The introduction briefly describes the pathogenesis, classification, diagnosis and modern treatment possibilities. In Africa leprosy is considered endemic. The World Health Organization estimates the total number of cases at 3.5 million. Over the last 20 years, however, the recorded number of cases has decreased dramatically. Increasing mobility on the part of the population, relocation from countryside to the cities, and a tendency towards urbanization are introducing a new dimension to leprosy distribution and the fight against the disease in Africa. Despite the not-inconsiderable financial, material and human resources that have so far been made available--mostly from outside the country--only a small percentage of the presumptive number of leprosy sufferers are receiving an adequate, modern combination therapy. This means that leprosy continues to represent a serious public and individual health problem in Africa.

[Leprosy. Pathogenesis--classification--diagnosis--treatment]

Leprosy (hanseniasis) is caused by chronic infection with Mycobacterium leprae (M. leprae). The disease involves primarily the superficial peripheral nerves and the skin, but almost any organ can be affected. The clinical features vary and are determined by the host's immune response to the infection. A distinction is made between multibacillary and paucibacillary forms of leprosy. The multibacillary forms are lepromatous, borderline-lepromatous and borderline-borderline leprosy; the paucibacillary forms are tuberculoid and borderline-tuberculoid leprosy. The clinical features and the histological picture depend on the patient's immune response. Because effective chemotherapy has become available, leprosy can now be cured, and frightening disabilities are therefore preventable.

Does dexamethasone suppress the Mazzotti reaction in patients with onchocerciasis?

The Mazzotti reaction is a frequent complication in patients with onchocerciasis being treated with diethylcarbamazine (DEC); and more severe manifestations of this reaction may be unacceptable in many patients. It has recently been demonstrated that prednisone modifies the severity of this reaction and reduces the microfilaricidal activity of DEC. A clinical trial was performed at the National Leprosy Training Center in Wau, Sudan, to evaluate the clinical and histologic effect of the use of corticosteroids in patients receiving DEC. Administration of a low dose of dexamethasone (3 mg/day), begun after onset of the Mazzotti reaction, modifies the progression of the Mazzotti reaction without interfering with the microfilaricidal efficacy of DEC. Pretreatment with low-dose dexamethasone--prior to beginning DEC therapy--prevents the development of the Mazzotti reaction and greatly reduces the microfilaricidal activity. Administration of diphenhydramine, after onset of the Mazzotti reaction, has no effect on the course and intensity of the Mazzotti reaction nor on microfilaricidal activity. We recommend that low-dose corticosteroids be administered in conjunction with DEC--after onset of the Mazzotti reaction--and that they be tapered rapidly.

[Onchocerciasis. Transmission--clinical aspects--diagnosis--treatment--immune relations]

Onchocerciasis is recognized as one of the most important filarial infections of man that involve grave dermatological disorders. The World Health Organization estimates that a total of 40 million people are suffering from this disease. Onchocerciasis means grave socioeconomic problems with very negative effects on general development in most regions where it is endemic. It often forces people to leave fertile agricultural valleys in an attempt to escape the disease and the flies that carry it. Though onchocerciasis has been known to medicine for over 100 years, it is only recently that it has started to be dealt with scientifically. In the last decade more has been learned about the parasite itself and about the medical aspects of infestation with it. This paper presents the mechanism of transmission, the clinico-epidemiological extent, the methods of diagnosis currently available, the immune response and the problems of both individual therapy and disease control.

[Skin diseases in Sierra Leone]

Today there is no Third World country in Africa that offers sufficient basic services for skin diseases. This paper describes the distribution and clinical aspects of skin diseases in school children, soldiers, the city population and villagers of Sierra Leone. Poverty-linked types of dermatosis play a major role throughout the country. The high prevalence rates and clinical degree make skin diseases a severe public health problem in Sierra Leone.

[Differential diagnosis of leprosy in developing countries--the skin and oral cavity]

There are some skin diseases which are frequently mistaken for leprosy and in consequence, often treated like it for a long period of time. The rate of false diagnoses is especially high in leprosy control programs of developing countries. However, a wrong diagnosis of leprosy can mean psychological disaster to the patient because of the stigma still attached to leprosy. According to the literature and our own observations in Sierra Leone, Ethiopia, and the Sudan, we present data on the differential diagnosis of leprosy concerning the skin and oral cavity.

A diagnostic "patch test" for onchocerciasis using topical diethylcarbamazine

There is great need for a simple, inexpensive, and sensitive diagnostic test for onchocerciasis, especially in endemic areas where trained personnel and laboratory facilities are limited. Diethylcarbamazine (DEC) was applied as a "patch test" to the skin of 45 patients with onchocerciasis in the Southern Sudan. 75 tests were done on these 45 patients, and 69 (92%) were positive. A positive reaction was a papular eruption beneath the patch. Histopathological studies of the skin beneath the patch revealed the microscopic features of a severe Mazzotti reaction, including degenerating microfilariae in the upper dermis and within epidermal eosinophilic abscesses.

[Cutaneous Leishmaniasis in Africa. Classification-clinical picture-treatment]

Vast travelling nowadays into warm subtropical and tropical regions demands more knowledge about infectious diseases outside our temperate climate. A leishmaniasis infection in Europeans is no rarity today because of its vast distribution in Africa. Cutaneous leishmaniasis is now considered a spectral and polar disease not unlike leprosy, caused by the leishmania parasite but also influenced by the host's immune response and intolerance. Therefore, diagnosis and treatment of a cutaneous leishmaniasis request an immunopathohistological view of the case.

[Leprosy. Classification--clinical aspects--diagnosis--therapy]

This paper reports on the causative organism of M. leprae, its mode of transmission, its classification into polar and interpolar forms, its diagnostic methods including skin smear, skin and nerve biopsy as well as on its treatment. The leprosy reaction presents a main complication of leprosy and can be considered as an emergency. Its pathomechanism, symptoms and treatment are mentioned.

[A case of cutaneous larva migrans in general practice]

Creeping eruptions are caused by the presence of larvae of certain nematodes in human skin. The disease is found in tropical and subtropical regions and therefore of great interest to travellers as well as to physicians examining people returning from these countries. The diagnosis of creeping eruption is relatively simple because of the characteristic clinical picture. Early lesions, however, may resemble a variety of other skin conditions. This paper deals with a case of creeping eruption in an European patient who consulted me in my general practice in southern Germany.