ARC syndrome: an expanding range of phenotypes

Aim-To describe the clinical phenotype in infants with ARC syndrome, the association of arthrogryposis, renal tubular acidosis, and cholestasis. Methods-The medical records for six patients with ARC syndrome were reviewed, presenting over 10 years to three paediatric referral centres. Results-All patients had the typical pattern of arthrogryposis. Renal Fanconi syndrome was present in all but one patient, who presented with nephrogenic diabetes insipidus. Although all patients had severe cholestasis, serum gamma glutamyltransferase values were normal. Many of our patients showed dysmorphic features or ichthyosis. All had recurrent febrile illnesses, diarrhoea, and failed to thrive. Blood films revealed abnormally large platelets. Conclusions-ARC syndrome exhibits notable clinical variability and may not be as rare as previously thought. The association of Fanconi syndrome, ichthyosis, dysmorphism, jaundice, and diarrhoea has previously been reported as a separate syndrome: our observations indicate that it is part of the ARC spectrum.