Neurofibromatosis is a genetic autosomal dominant disorder consisting in cutaneous, neurologic, ophthalmologic and tumoral signs. But other disorders that can mimic neurofibromatosis should be excluded.
A 10-year-old girl, from consanguineous gipsy parents, was admitted for anemia. Family history showed a sister who died due to cerebral tumors at the age of 3. The personal medical history was insignificant.
The clinical examination revealed more than 6 „cafe au lait” spots larger than 0,5cm and multiple axillary freckling, signs which support the diagnosis of neurofibromatosis. The clinical exam of the parents was normal. Laboratory explorations showed a normochromic, normocytic anemia, with normal ferritin level, a folic acid deficiency, normal liver and kidney function, but also immunological abnormalities: IgA, IgG2 and IgG4 deficiency, poor response to vaccination, low memory B cells and a normal number of T, CD4+, CD8+ and NK cells. Ophthalmologic examination was normal. Multiple tumors with the diameter between 0,5 and 4 cm were noted during the cerebral MRI-scan. In evolution, she displayed recurrent episodes of seizures. The cerebral biopsy revealed a diffuse astrocytoma IDH mutant and she started chemotherapy. Taking in account the consanguinity, family history and the negative clinical exam of the parents we performed genetic exam – WES that revealed a pathogenic homozygous c.2653A>T mutation in MSH6 gene, parents being carriers for the same mutation.
In atypical cases of neurofibromatosis associating immunological abnormalities, DNA repair syndromes must be excluded. A correct diagnosis allows genetic counseling and monitoring for the cancer development in other members of the family.