Type 4 Waardenburg syndrome (also called Waardenburg-Shah syndrome) is characterized by symptoms of Hirschsprung's disease in addition to the classic features of hearing loss and pigmentation abnormalities.
[Effects of a vitamin B complex on functional recovery after nerve injury (author's transl)]. Hasegawa K, Mikuni N, Sakai Y. Functional recovery after nerve crushing was investigated in the following manner: Under pentobarbital anesthesia the sciatic nerve of the rat was crushed at the level of the hip (proximal crush) or the thigh (distal crush).
Nerve damage may in fact stem from a lack of sufficient B vitamins in the body, especially thiamin, B6 and B12, according to Prevention's Healing with Vitamins by Alice Feinstein. Those whose nerve damage stems from diabetes in particular can often benefit from B vitamin complex supplementation. Consult a doctor before supplementing with B vitamins higher than the recommended daily value, as doses of B6 above 200 mg have been shown to actually cause nerve damage.