Fever and rash, viral causes

A problem that occurs during or after a trip does not necessarily need to have a causal connection with that trip.

• Dengue is probably the most frequent arbovirosis. The disease is often associated with a fine, maculopapular skin rash that disappears when pressure is applied. This is different from the petechiae and ecchymoses that can occur with haemorrhagic dengue.

• Mononucleosis infectiosa is frequently associated with a maculopapular rash. This can be triggered by administration of amoxycillin. Lymphadenopathy, sore throat, mild splenomegaly and abnormal lymphocytes in a thin blood smear early in the infection are suggestive for the diagnosis.

• Coxsackie viruses and other enteroviruses can likewiss cause fever and cutaneous rash. The mouth is also affected in hand-foot-mouth disease (most often caused by Coxsackie A16). The enanthema is vesicular or ulcerative. In 75% of the patients mildly painful vesicular or papulovesicular lesions occur on the palms of the hands and on the soles of the feet.

• Erythema infectiosum (fifth disease) is caused by parvovirus B19. The rash usually starts on the cheeks ("slapped cheeks disease"). It is a cosmopolitan self-limiting disease that mainly affects children. Severe haematological complications (bone marrow aplastic crisis) can occur in sickle cell patients.

• Roseola infantum or exanthema subitum (sixth disease, herpes virus 6) is a viral disease of young children. The rubelliform rash appears whan the fever abates and disappears after the third or fourth day. There is a leukopenia with relative lymphocytosis. Only symptomatic therapy is necessary.

• Measles and rubella, thanks to vaccination, have become very rare. The general symptoms of rubella are limited and post-auricular and suboccipital lymphadenopathy often occur. In the early phase of measles Koplik spots may be present in the mouth. The general symptoms in measles are much more serious than in rubella. Corneal lesions frequently occur in patients with measles in developing countries. Desquamation follows after the acute phase. In cases of malnutrition the mortality of measles is considerable.

• Varicella is quite frequenly seen in children and in non-immune adult tourists. Varicella is caused by a first infection with the varicella zoster virus. The cutaneous rash is initially maculopapular, but quickly becomes typically vesicular and finally gives rise to scabs. The lesions are found in various stages (in contrast to the now eradicated variola major). Lesions also occur on the oral mucosa. Disseminated herpes simplex, monkeypox (very rare) and rickettsial pox can resemble this disease.

• Hepatitis B is occasionally complicated in children by an acute non-pruritic cutaneous rash that disappears spontaneously after 2 to 8 weeks (Gianotti-Crosti-syndrome or acrodermatitis papulosa eruptiva infantilis). The preferred location is on cheeks, buttocks and extremities (not on flexor side of elbows and knees). There are usually swollen lymph nodes. Gianotti and Crosti also described a cutaneous rash that can occur after infections with various other viruses (Coxsackie A 16, parainfluenza B, etc) or after vaccination (poliomyelitis, BCG, tetanus). An acute and slightly pruritic symmetrical exanthema consisting of oedematous, papular or papulovesicular lesions can occur on cheeks, extremities, palms of the hands and soles of the feet, as well as on the torso and on the flexor sides of elbows and knees. There is no enanthema.

• Ebola or Marburg virus. Patients infected with Marburg or Ebola virus exhibit sudden fever, severe headache and muscle pain, malaise, conjunctivitis, occasionally a papular rash, dysphagia, bloody diarrhoea followed by diffuse haemorrhages (especially the mucosae), delirium, shock and ARDS (acute respiratory distress syndrome). Only 5% of the patients exhibit jaundice. In addition to a functional blood platelet disorder there is always thrombocytopenia. Initially there is lymphocytopenia with acute immunosuppression, followed later by neutrophilia. Histologically there are necrotic foci in various organs (testes, kidneys, liver).

• Monkeypox. Monkeypox is a very rare infectious disease, caused by an orthopox virus, morphologically identical to variola. Transmission can occur through contact with infected monkeys or other infected animals (e.g. giant rats, prairy dogs). Secondary cases can occur, though spread from person to person does not generally occur very frequently. Individuals vaccinated against variola are also protected against monkeypox. An incubation of 5-17 days is followed by an influenza-like syndrome. Approximately 2-3 days after appearance of this syndrome a papular skin rash appears, progressing to pustular lesions (including palms of hands and soles of feet). The pustules then often exhibit a central depression. Scab formation occurs and after 10 days these lesions may show a small scar. Substantial lymphadenopathy can occur. Treatment is symptomatic. Cidofovir may be active against this virus. This medicament can be administered intravenously.

• Cowpox: Cowpox is rare and used to occur only in Europe and Russia. The infection occurs in small mammals, cats and mice, and can sometimes appear in large animals, such as cattle and elephants. Humans can also be infected. The majority of cases exhibit vesiculopustular lesions on hands or face. The lesions ulcerate and subsequently develop a black crust. Differentiation from anthrax, mycosis, rickettsial chancre and tularaemia is necessary. Cowpox is caused by an orthopox virus and is related to variola and vaccinia virus. It is thought that infection occurs by direct contact with an infected animal such as a cat or a milking cow with lesions on her udder. The infection almost always remains localised at the site of inoculation. Rarely, there is dissemination via the lymphatics. Disseminated cowpox is extremely rare, but does exist. Spontaneous recovery is the rule with only a small residual scar as a consequence. Of three patients who have had severe infection, there were two with atopic eczema and a third had high fever for which he received steroids.

Category: Medicine Notes