Table 1. Comparative table of the two disorders' various features*.
| NEUROFIBROMATOSIS | PROTEUS SYNDROME |
| Prevalence | |
| Frequent: 1/3,000–1/4,000 live births worldwide | Extremely rare: <1/1,000,000 live births worldwide |
| Equally prevalent in males and females | Two males for every female |
| Gene | |
| NF1, chromosome 17 (17q11.2) | Unknown |
| Transmission | |
| 50% hereditary (autosomal dominant) | Sporadic |
| 50% sporadic (de novo mutation) | Postzygotic somatic mutation (embryonic lethal in non-mosaic form; never with diffuse involvement of the entire body) |
| Diagnostic Criteria | |
| An individual has NF1 if at least two of these criteria are present. | An individual has Proteus syndrome if the three general criteria plus one criterion from category A or two from category B or three from category C are present. |
| General Criteria | |
| 1. Café-au-lait spots (at least 6): Diameter >1,5 cm after puberty; >0,5 cm before puberty | 1. Mosaic distribution of lesions |
| 2. Neurofibromas (at least 2 of any types) and/or one or more plexiform neurofibromas | 2. Sporadic occurrence |
| 3. Axillary and/or inguinal freckling | 3. Progressive course |
| 4. Optic gliomas | Category A |
| 5. Lisch nodules (2 or more) | 1. Cerebriform connective tissue nevus |
| 6. Characteristic osseous lesion (sphenoid dysplasia, thinning of long bone cortex with or without pseudoarthrosis | Category B (two required) |
| 7. First degree relative with NF1 | 1. Linear epidermal nevus |
| 2. Asymmetric, disproportionate overgrowth | |
| 3. Specific tumors before second decade | |
| Category C (all three required) | |
| 1. Lipomas or focal atrophy of adipose tissue | |
| 2. Capillary, venous, or lymphatic malformation | |
| 3. Facial features including dolichocephaly, a long face, down-slanting palpebrae, ptosis, depressed nasal bridge, anteverted nares, and open mouth position while at rest | |
| General clinical manifestations | |
| 1. High blood pressure | 1. Pulmonary abnormalities |
| 2. Scoliosis | 2. Renal abnormalities |
| 3. Malignant tumors | 3. Brain malformations |
| Cognitive and psychological problems | |
| 1. Attention deficit (with or without hyperactivity) disorder in 40% to 50% of cases | 1. Learning difficulties in 20% of cases |
| 2. Learning difficulties in 30% to 65% of cases | 2. Mental retardation in 10% to 15% of cases |
| 3. Slight mental retardation in 1% to 8% of cases (no consensus among authors) | 3. Psychological consequences of the disease |
| 4. Difficulty forming friendship in childhood | 4. Feeling of isolation |
| 5. Impact on quality of life | 5. Social stigmatization |
| 6. Difficulty establishing social relationships | 6. Courtesy stigma afflicts family members |
| 7. Psychological/psychiatric disorders | |
| 8. Esthetic considerations represent a psychological burden | |
*Adapted from Cohen, 1993; Hart, 2005; Biesecker, 2006, 2005, 2002; Turner, 2007; NIH, 1998.