Pigmentary diseases

Abnormalities of pigmentation are common and frequently produce great concern in patients presenting to primary care physicians. Although many pigmentary changes arise as a consequence of inflammatory skin disorders, it is important to differentiate a primary skin disease from postinflammatory changes. Early recognition of a pigmentary disease allows the clinician to begin appropriate therapy at a stage when medical intervention may be more effective. Although many skin disorders are mainly of cosmetic concern, the condition may be devastating psychologically, requiring the clinician to be sensitive to the overall impact of the disorder and treat it accordingly.     

Surgery in the tropics

The practice of surgery in the tropics provides experience in the management of a broad range of conditions without many of the aids now regarded as essential in developed countries. Clinical judgement must play a greater role but the often advanced stage of disease at presentation may lessen the need for investigations and limit the treatment options. Subspecialisation is well advanced in many countries but most of the surgery performed in the world is by people not long out of medical school, much less by general surgeons. Western trained surgeons need to take into account local cultural attitudes to disease and disease management. Busy practical surgeons in tropical areas have made notable contributions to knowledge and practice. Burkitt and Huckstep, both in Kampala, and Brand in Vellore are outstanding examples. Each of these men was heavily dependent on a great many comparatively untrained but skilled paramedical workers.     

Madagascar: esophagogastroduodenoscopy. Descriptive analysis of 12,000 examinations and problems encountered in the tropics

Regional cerebral blood flow was measured with H2(15)O-positron emission tomography during the performance of visually presented calculation tasks to clarify cortical areas involved in arithmetic operations. The findings on a calculation task were compared with those on a covert reading task and with those of a fixation control task. Region of interest-based analysis showed that the left prefrontal area was activated in visual calculation relative to covert reading and the posterior superior temporal gyrus including part of Wernicke's area was activated in calculation relative to fixation control. The role of the prefrontal area in computation (arithmetic operations) and that of the posterior superior temporal gyrus in both comprehension of the stimuli and computation were suggested.     

Imported dengue fever following a stay in the tropics

We report on a tourist returning from Thailand, who presented with classical dengue fever. While in Thailand a 36-year-old Swiss female laboratory assistant suddenly developed fever, devastating headache, retro-ocular pain, myalgia and arthralgia, photophobia, nausea and diarrhea. In addition she suffered from epistaxis, urogenital and skin bleeding, and a morbilliform exanthema. After her return to Switzerland we noted lymphadenopathy and splenomegaly, enanthema and laboratory findings of mild hepatitis, thrombocytopenia and leukopenia. The diagnosis of dengue virus infection was verified serologically. Apart from a long lasting convalescent asthenia we observed restitutio ad integrum within days under symptomatic therapy. Epidemiological clinical and diagnostic aspects of dengue virus infection are discussed.     

Mycetoma of the foot; a disease from the tropics

Two patients, a Surinamese man aged 50 and a Surinamese woman aged 56 exhibited a mycetoma of the foot, 30 and 28 years, respectively, after a local injury. Pathological examination revealed an aspecific chronic granulomatous inflammation. As causative agents a Fusarium species and a Cladosporium normodendrum, respectively, were cultured. The treatment consisted of curettage of fistulous ducts and administration of itraconazole.     

Methionine supplementation of low protein diets for broiler chicks in the tropics

In the first experiment, diets containing 14, 16, 18, 20, 22 or 24% protein with no methionine supplementation were tested, while in the second experiment diets containing 16, 18 and 20% supplemented with methionine to give 90, 100 or 110% of the recommended N.R.C. levels were compared with an unsupplemented 24% protein diet. 2. Methionine supplementation of the low protein diets stimulated faster gains than the unsupplemented diets but not enough to surpass the response to the 24% protein control diet. 3. It was concluded that a high protein diet unsupplemented with methionine was more economical to feed to broilers than supplemented low protein diets.     

Return from the tropics: relevant diagnosis and rational therapy

Gastrointestinal disorders, particularly diarrhoea, are the main reason to consult a physician after travelling to the tropics. Although mostly of infectious origin specific pathogens frequently cannot be demonstrated. As the majority of acute diarrhoeal episodes resolve without any specific therapy, bacterological and parasitological investigations should initially be ordered with reserve and economically. Fever after a stay in the tropics has to be always a matter of concern as it could be the expression of a potentially dangerous infection, e.g. falciparum malaria. The primary objective must be the exclusion of potentially life-threatening infections requiring a specific treatment. Numerous asymptomatic travellers returning from the tropics want their physicians to exclude an inapparent exotic infection. The value of such check-ups can be questioned, and there are just a few rational investigations in this particular context.     

Febrile status in a traveler returning from the tropics with right-sided upper abdominal pain

This is a case report of a patient who presented multiple liver abscesses with Entamoeba histolytica five weeks after returning from an one-month trip to Thailand. This makes clear that a febrile patient returning from the tropics may not only be suspected of malaria, but that we should think about other possible febrile diseases. Respecting the incubation period and other clinical symptoms and signs, we are in most of the cases able to reduce the differential diagnosis to only a few possible ones. Diagnosis, treatment and follow-up are discussed. It is important to know that ultrasonography offers much help in the follow-up but that it may last months or more than one year to normalize the sonographic feature.     

A comparison of two methods of oestrous synchronisation of hair sheep in the tropics

In the last years, the occurrence of pesticides and other chemicals in groundwater has been confirmed. The herbicide atrazine is among the pesticides most frequently detected in groundwater. In groundwater samples from the United States atrazine concentrations reached levels up to 10 micrograms/1. In our lysimeter experiments with radioactive labelled terbuthylazine we measured 2.87-4.20% of the applied radioactivity after 1160 days in the leachate.     

Pigmentary changes after pulsed dye laser treatment in 125 northern European patients with port wine stains

A child with cystic dysplasia of the testis (CDT) that presented as a solid mass by ultrasound imaging is reported. The child also had ipsilateral multicystic dysplasia of the kidney (MCDK). A search of the literature revealed that unilateral renal agenesis (URA) is commonly associated with CDT. It is possible that CDT, MCDK, and URA share a common pathogenesis. Cystic changes in the epididymis were found in the patient and might be more frequently associated with CDT than previously reported. CDT should be considered in the differential diagnosis of a solid testicular mass detected by ultrasound.     

Mite allergy in the tropics: sensitization to six domestic mite species in Cartagena, Colombia

Sensitization to the domestic mites Blomia tropicalis, Chortoglyphus arcuatus, Lepidoglyphus destructor and Aleuroglyphus ovatus was investigated in 77 subjects with clinical symptoms of asthma and/or allergic rhinitis and a positive skin prick test (wheal > or = 3 mm) to Dermatophagoides pteronyssinus and/or D. farinae. Seventy patients were skin test-positive to D. pteronyssinus and 73 to D. farinae. Serum samples from 29 nonallergic, skin test-negative individuals were used as negative controls. Specific IgE was determined by RAST and the results expressed as the % of the total counts bound (% TCB). A positive result (> or = 1% TCB) to D. farinae was detected in 89.6% of subjects, to B. tropicalis in 80.5%, to D. pteronyssinus in 75.3%, to C. arcuatus in 71.4%, to A. ovatus in 68.8% and to L. destructor in 59.7%. None of the controls had a positive RAST to any of the mite species. Different IgE binding patterns were observed among these subjects, suggesting sensitization to unique as well as common allergens in the different mite species. Sensitization to Pyroglyphidae (D. pteronyssinus and D. farinae) and non-Pyroglyphidae mites (B. tropicalis, C. arcuatus, L. destructor and A. ovatus) is common among allergic individuals in Cartagena. Extracts of these mites may be needed for a more accurate diagnosis and effective treatment of respiratory diseases due to mite allergy in tropical environments.     

Skin problems in the traveler

Skin lesions are common in travelers and include a mix of mundane dermatologic problems and rare diseases acquired only in remote or tropical regions. The morphology, distribution, and progression of the lesions are useful in assessing possible causes. Early in the evaluation it is important to determine whether the patient might have a process that is rapidly progressive, treatable, or transmissible. In addition to routine laboratory studies, biopsy and serologic tests are often necessary to confirm a specific diagnosis.