A survey of 170 patients with a diagnosis of palmoplantar pustulosis (PPP) has been undertaken. Detailed family histories of our patients were compiled, dermatological and rheumatological examinations were made. Radiography was performed in patients with clinical suspicions of spinal and/or sacroiliacal, sternoclavicular and sternocostal joint involvement. Active chest-wall symptoms were screened by scintigraphy. Twenty-five patients (16 females, 9 males, with an age range of 32-66, mean 51 years) had some rheumatic complaints. Fifteen of them (60%) had anterior chest-wall involvement, 6 (24%) sacroiliitis (3 of whom also had AS) and 11 (44%) peripheral arthropathy. Six other patients suffered from transient and migratory joint pain. The joint disease was mild in all but 6 cases. Laboratory tests showed increased ESR in 6 patients (24%); only 3 of these patients had elevated CRP. A slightly elevated haptoglobin and/or orosomucoid were found in 12 cases (48%). Elevated IgA was present in 4, IgG in 2 and IgM in 1 patient. Fungal and bacteriological cultures of the skin were negative. A family history of psoriasis was present in 4 patients (16%), of psoriatic arthropathy in 1 patients (4%) and of PPP in 2 patients (8%). Six patients (24%) had concomitant psoriasis. No association between PPP H1a-AC antigens was found. A high incidence of HLA-B27 antigen, present in 8 patients (32%), was documented. A similar association with HLA-B27 has been found in patients with psoriatic arthritis (16). The feeble association with HLA-B13,-17,-37 and CW6 found in psoriasis was not present.(ABSTRACT TRUNCATED AT 250 WORDS)