Abstract
Cyclic neutropenia (CN) is a rare disease, primarily affecting neutrophil production. Autosomal dominant and sporadic cases of CN are caused by mutations in the gene for neutrophil elastase. A 16-year-old girl has recurrent aphthous ulceration and hematuria occurring with these episodes. The clinical features and serial peripheral blood studies establish a diagnosis of CN at the age of one month. Hematuria shows waxing and waning at times of oral ulceration and neutropenia. Serum immunoglobulins are elevated, with a disproportionate elevation of IgA. The kidney tissue specimens show diffuse mesangial involvement with mesangial IgA and C 3 deposition and electron dense deposits in the mesangium, consistent with IgA nephropathy. Her renal function remains well with oral prednisolone therapy. Patients with CN increase the likelihood of significant mucosal infection and therefore the probability of overt and symptomatic IgA nephropathy. A long-term administration of granulocyte-colony stimulating factor may immunologically contribute to the development of glomerular diseases.