Reinfection with Chlamydia pneumoniae may induce isolated and systemic vasculitis in small and large vessels.

It is a common clinical experience that the onset of the so called non infectious vasculitides is often preceded by upper respiratory tract symptoms. A specific agent is only occasionally recovered. We report five cases in Sweden with manifestations of vasculitis from different organs. In three of the five patients the onset was preceded by upper respiratory tract symptoms. All patients had serologic findings indicating Chlamydia pneumoniae infection and all required corticosteroid treatment for symptomatic recovery. One was diagnosed as an aseptic meningitis. Another was diagnosed as a cerebral arteritis, probably a variant of a giant cell arteritis. A third patient had symptoms similar to a polymyalgia rheumatica engaging the thighs. Two patients had an acute myocardial infarction. One of them had Cogan's syndrome. The other also had pulmonary and hepatic engagement and an elevated level of anti basement membrane IgM antibodies, though not to the Goodpasture antigen. He had no renal involvement. The diagnosis of Chlamydia pneumoniae infection was based on the detection of species-specific IgA, IgG and IgM antibodies to Chlamydia pneumoniae using microimmunofluorescence technique, MIF. Four of the 5 cases exhibited a fourfold increase in antibody titers, and the fifth case was found to have high levels of IgG and IgA antibodies, suggesting recent infection. Investigations for other infectious agents were negative in all patients. The serologic findings in those patients are consistent with a pattern of reinfection with Chlamydia pneumoniae. We therefore suggest that reinfection with Chlamydia pneumoniae may induce isolated and systemic vasculitis in virtually any organ of the body.

Ambulatory 24-hour blood pressure and peptide balance in hemodialysis patients.

Blood pressure regulation during intermittent hemodialysis treatment involves many different mechanisms. Eight normotensive patients without antihypertensive drugs on intermittent hemodialysis treatment, mean age 50 years, were studied with 24-hour blood pressure measurements. Atrial natriuretic peptide (ANP) and neuropeptide Y (NPY) were determined concomitantly. Eight control individuals matched for age and sex were investigated in the same way. A significant increase of both systolic and diastolic blood pressure, heart rate and pathological circadian rhythm was seen among the dialysis patients. High levels of ANP were found before and after dialysis. NPY showed steady state levels through the 24 hours and did not differ between the two groups. Overhydration is a probable cause of the disturbed blood pressure regulation and increased ANP-values.