A case-control study of necrotizing fasciitis during primary varicella

Objective. An increase in the incidence of necrotizing fasciitis (NF) occur ring in previously healthy children with primary varicella was noted in the Washington State area between December 1993 and June 1995. Our objective w as to investigate ibuprofen use and other risk factors for NF in the settin g of primary varicella. Methods. Case-control study. Demographic information, clinical parameters, and potential risk factors for NF were compared for cases and controls. Cas es of NF were analyzed to identify potential determinants of NF complicated by renal insufficiency and/or streptococcal toxic shock syndrome. Multivar iate logistic regression was used to evaluate the association between ibupr ofen use and NF. A case was defined as a child with NF hospitalized within 3 weeks of primary varicella (n = 19). Controls were children hospitalized with a soft tissue infection other than NF within 3 weeks of primary varice lla (n = 29). Odds ratios (ORs) of ibuprofen, as well as other potential ri sk factors were evaluated. In addition, demographic and clinical data as we ll as other potential risk factors were compared between cases and controls . Results. After controlling for gender, age, and group A streptococcus isola tion, cases were more likely than controls to have used ibuprofen before ho spitalization (OR, 11.5; 95% confidence interval, 1.4 to 96.9). In most chi ldren, ibuprofen was initiated after the onset of symptoms of secondary inf ection. Children with NF complicated by renal insufficiency and/or streptoc occal toxic shock syndrome were more likely than children with uncomplicate d NF to have used ibuprofen (OR, 16.0; 95% confidence interval, 1.0 to 825. 0). Children with complicated NF also had a higher mean maximum temperature (40.9 degrees C vs 39.3 degrees C), and a longer mean duration of secondar y symptoms (1.7 days vs 0.6 days) before admission than children with uncom plicated NF. Conclusion. Ibuprofen use was associated with NF in the setting of primary varicella. Additional studies are needed to establish whether ibuprofen use has a causal role in the development of NF and its complications during va ricella.