Histopathological evaluation showed myocarditis in a higher than expected proportion of cases. In one such case, which we studied before the sudden unexpected death occurred, the victim had suffered a Chlamydia pneumoniae infection verified by serology, and a nucleotide sequence was found in the heart and lung by means of the polymerase chain reaction (PCR) that hybridized with a probe specific for that organism. Male Swedish orienteers do not, however, seem to have an increased rate of exposure to this agent. No further sudden unexpected deaths among young orienteers have occurred over the past 3.5 years. At the beginning of that period, attempts were made to modify training habits and attitudes.

Echocardiography was used to assess normal values in the right and left ventricular cavity and wall in 127 male elite endurance athletes. M-mode and two dimensional measurements of left ventricle and left and right atria were also obtained. All subjects were high-performance orienteers, cross-country skiers and middle-distance runners. They all had a normal electrocardiogram at rest and no echocardiographic evidence of heart disease. With the use of multiple right ventricular cross-sections and two-dimensional measurements, we found a significantly greater right ventricular inflow tract and right and left atrial measurements in endurance athletes compared with earlier studies of normal, active subjects. The right ventricular free wall was slightly thicker than reported in normal active subjects but the differences were small. Left ventricular diastolic diameter was consistent with previous reports of endurance athletes. Of the 127 subjects, 13% had left ventricular wall thickness above 13 mm but none of the athletes had wall thickness above 15 mm. These data suggest that cardiac enlargement occurs symmetrically in both right and left cavities, probably reflecting increased haemodynamic loading, a mechanism by which athletes sustain a high cardiac output during exercise.

Chlamydia pneumoniae has previously been demonstrated in the atherosclerotic lesions of various arteries, including the coronary arteries, and has been proposed to play a role in the pathogenesis of atherosclerosis. A prospective study of the incidence of C. pneumoniae in the sclerotic valves of patients undergoing aortic valve replacement because of aortic stenosis and in the aortic valves of cases dying of non-cardiac reasons and undergoing forensic autopsy was undertaken. The results were correlated to serological markers of past (IgG) or persistent (IgA) C. pneumoniae infection. C. pneumoniae, as determined by the polymerase chain reaction (PCR), was detected in the aortic valve in 19/39 (49%) patients and in 1/11 (9%) autopsy controls (p = 0.018) and confirmed by electron microscopy in one patient. There was no significant difference in the incidence rate of IgG or IgA antibody positivity between PCR-positive and PCR-negative cardiac patients. These results extend the hypothesis of a pathogenic role of C. pneumoniae in atherosclerosis to include also aortic valve sclerosis.

A 34-year-old splenectomized man presented with fever, myalgia and dysuria. His condition rapidly deteriorated, he became anuric and developed severe haemolytic anaemia, thrombocytopenia and fibrinolysis. Peripheral blood smears revealed intra-erythrocytic parasites consistent with Babesia divergens in 40% of the erythrocytes. The diagnosis was confirmed by gerbil inoculation and by a significant rise in antibody titer. Blood exchange transfusion reduced the number of babesia infected erythrocytes to 1%. Parenteral therapy with a combination of quinine and clindamycin eradicated parasitaemia after 10 days of treatment and the patient rapidly improved. Renal failure necessitated haemodialysis for one month, whereafter the patient made a full recovery. Human babesiosis is a rare disease, but with a potential fatal outcome and should be considered as a diagnostic alternative in splenectomized and otherwise immunocompromised individuals with severe febrile illnesses.

We determined whether ketoconazole prophylaxis might reduce Candida colonization and infections in adult patients with acute leukaemia. During first-remission induction therapy 50 patients were treated with 200 mg ketoconazole administered orally daily, while 57 patients received placebo in a double-blind, randomized trial. The duration of severe neutropenia (granulocytes less than 0.1 x 10(9) l-1) represented 36% of the study period in the ketoconazole group and 26% in the placebo group (P = 0.043). Although fewer patients presented with positive Candida surveillance cultures and serological evidence of Candida infection in the ketoconazole group compared to the placebo group, two candidaemias and one Trichosporum fungaemia were observed in the ketoconazole group. Moreover, significantly more bacteraemias were noted in the ketoconazole group (n = 37) than in the placebo group (n = 21) (P = 0.004). Thus, although oral ketoconazole prophylaxis might be associated with less Candida colonization and fewer seroconversions, it also resulted in more bacteraemias and longer duration of severe neutropenia, suggesting that caution should be exercised when ketoconazole (or related drugs) is given to this group of immunocompromised hosts.