Clinical and laboratory correlates of selective autonomic dysfunction due to Ross syndrome

Ross syndrome is diagnosed by the presence of the characteristic triad of segmental anhidrosis, depressed deep tendon reflex, and tonic pupils. It is a rare, misdiagnosed autonomic disorder with less than 80 cases reported in the world literature. Two representative cases of Ross syndrome are presented with their laboratory correlates and relevant review of literature. Both cases (aged 35 and 58) presented with complaint of decreased sweating over one half of the face and ipsilateral upper limb and trunk and contralateral lower limb. There was compensatory increased sweating and hyperpigmentation over the remaining parts of the body. The duration of symptoms was 2 years and 15 days. The patients had variegated skin color as per the above distribution and hyporeflexia in lower limbs. One patient also had Holmes-Adie pupil. Iodine test showed hypohidrosis in the described areas, which was confirmed by skin biopsy in both cases. The patients were treated symptomatically with incomplete relief. The authors aim to highlight this rare disorder that can be one of the causes of pathological sweating encountered in general practice and the challenges in its management.