FACTORS ASSOCIATED WITH PNEUMOCYSTIS-CARINII PNEUMONIA IN WEGENERS GRANULOMATOSIS

Objective-To determine the factors associated with the occurrence of P neumocystis carinii pneumonia (PCP) in Wegener's granulomatosis (WG). Methods-We retrospectively compared a group of 12 patients with WG and PCP (PCP group), with 32 WG patients without PCP followed over the sa me period in the same centres (control group). Results-The mean delay of onset of PCP after the start of the immunosuppressive therapy was 1 27 (SD 128) days. Before treatment, the clinical and biological featur es of the two groups were similar, except for the mean lymphocyte coun t which was lower in the PCP group than in the control group (1060/mm( 3) v 1426/mm(3); p = 0.04). During treatment, both groups were lymphop enic. There was a significant difference between the lowest Creteil, F rance absolute lymphocyte count in each group (244/mm(3) in the PCP gr oup v 738/mm(3) in the control group; p = 0.001). During the first thr ee months of treatment, the lymphocyte count was less than 600/mm(3) a t least once in 10 of the 12 patients in the PCP group and in 11 of th e 32 patients in the control group (p<0.01). The mean cumulative dose of cyclophosphamide was greater in the PCP group than in the control g roup at the end of both the second (1.55 mg/kg/day v 0.99 mg/kg/day; p = 0.05) and the third (1.67 mg/kg/day v 0.97 mg/kg/day; p = 0.03) mon ths. However, in multivariate analysis, the only two factors independe ntly and significantly associated with the occurrence of PCP were the pretreatment lymphocyte count (p=0.018) and the lymphocyte count three months after the start of the immunosuppressive treatment (p = 0.014) . Conclusions-The severity of lymphocytopenia before and during immuno suppressive treatment is the factor best associated with PCP in WG.