INSIDIOUS RECURRENT ABDOMINAL PAIN

Porphyrias are a group of inherited metabolic disorders of heme biosynthesis leading to excessive accumulation and excretion of porphyrins.The variable clinical manifestations may determine a delay in the diagnosis, followed by a possible negative clinical outcome. We describe a case of a 14-year-old girl with ShwachmanDiamond syndrome (SDS) and epilepsy admitted with severe cyclic abdominal pain not responsive to antalgic therapy, localized in the epigastric area, irradiating to the whole abdomen and the back, associated to aspecific symptoms (diarrhea, fever,vomiting). During hospitalization, the girl was asymptomatic. We excluded infectious, autoimmune, endocrinological causes, a relapse of SDS and performed a screening for porphyria that resulted negative. After each attack, she referred presenting urinary retention followed by hyperchromic urines, anxiety and paresthesias. Past clinical data showed hyponatremia, tachycardia and hypertension. Eventually, increased values of ALA (8.21 mg/l) and PBG (3.96 mg/l) were found; exposure of fresh urines to sunlight caused a change of their color. Finally, genetic analysis was negative. These findings allowed the diagnosis of porphyria, therefore we prescribed a normocalorichyperglucidic diet andpreventive glucose solutions in stressing situations, with regression of symptoms. Acute porphyrias present with life-threatening crisis secondary to the injury of central, peripheral and autonomic nervous system. They can be triggered by drugs, alcohol, infections, reduced caloric intake, endogenous hormone cycles and stressing situations. The characteristic manifestations are severe cyclic abdominal pain, neurological or psychiatric symptoms and/or hyponatremia. Diagnostic is the assessment of plasmatic PBG/ALA, always increased during an attack, normal during remission. Treatment is human haemin although, in mild attacks, a diet with high carbohydrates and/or preventive glucose infusions is effective; a negative genetic evaluation should never exclude the diagnosis. It is important considering acute porphyria in the differential diagnosis of severe cyclic abdominal pain, particularly in subjects affected by different and/or rare clinical disorders.