Neurofibromatosis type 1 vasculopathy: when to screen?

Abstract

INTRODUCTION: Case Description. A male infant born after an uneventful pregnancy and delivery was admitted to the neonatology ward on the first day of life because of feeding difficulties. Parenteral nutrition was initiated and continued for two days. Abdominal ultrasound screening showed a vascular malformation in the liver, which was further investigated by magnetic resonance imaging, describing the lesion as an arteriovenous malformation. No other abdominal vascular lesions were found. Favorable progression of drinking behaviour allowed the child to be discharged home on day 8. The appearance of multiple brownish maculae on the back and trunk of the infant by the age of 3 months initiated diagnostic evaluation for neurofibromatosis 1 (NF1). Dermatologic evalution classified the lesions as typical café-au-lait maculae. No axillary or inguinal freckling was found. Ophthalmologic examination showed no abnormalities. Gene analysis revealed a mutation in the NF1 gene; which confirmed the clinical diagnosis of NF1. CONCLUSION Discussion. NF1 is an autosomal dominant disorder with a prevalence of one in 3000 individuals. NF1 diagnosis in patients with negative familial history can have significant delay due to the initial absence of at least two of the seven diagnostic criteria, as defined by the National Institutes of Health consensus statement. Significant vascular lesions are a rare but well-known feature of the disease and routine vascular screening is not recommended. NF1 vasculopathy includes a wide spectrum of vascular abnormalities. The most common lesions are aneurysms or stenoses of the aortic, renal and mesenteric arteries. Arteriovenous malformations are also part of the spectrum. Once a vascular abnormality has been identified screening for other lesions by non-invasive imaging of head, chest and abdomen is justified. Patients with NF1 vasculopathy have a reduced life expectancy when compared with NF1 patients without vasculopathy, especially when arteries of the heart or brain are involved