For making clinical diagnosis of neurofibromatosis, following two of the following features are necessary:

• A minimum of six café au lait spots larger than 1.5 cm in diameter in a postpubertal patient and larger than 5 mm in diameter in prepubertal patients

• Two or more neurofibromas of any type or one plexiform neurofibroma

• Freckling in the inguinal or axillary regions

• Optic glioma

• Two or more iris Lisch nodules by slit-lamp examination [nodular aggregate of dendritic melanocytes affecting the iris]

• A distinctive bony lesion

• A first-degree relative with a definitive diagnosis of neurofibromatosis