ACUTE PORPHYRIAS - DIAGNOSIS AND MANAGEMENT

To summarize recent information about acute porphyrias and to provide clinicians with a practical diagnostic and management approach, we rev iewed the pertinent literature and our clinical experience. The acute porphyrias are characterized by recurrent attacks of abdominal pain wi th or without additional manifestations of autonomic dysfunction or ne uropsychiatric symptoms. On the basis of the potential of these disord ers to affect the skin, they are further subdivided into neuroporphyri as and neurocutaneous porphyrias. During acute attacks, acute porphyri a is always associated with increased levels of urinary porphyrin prec ursors. Between attacks, patients with neurocutaneous porphyrias may h ave normal urinary porphyrins; therefore, stool porphyrins, which are invariably increased, are the most helpful. Latent disease can be dete cted by the measurement of either urinary and stool porphyrins or cell ular enzyme activity. Specific intravenous therapy with hematin has re sulted in biochemical remissions, but its clinical benefit remains con troversial. Measurement of urinary and stool porphyrins or porphyrin p recursors is critical for the diagnosis of clinically overt acute porp hyria. Enzyme assays are helpful in supporting the diagnosis but are b est used to identify family members with latent disease. Preventive me asures and supportive therapy are the mainstays of current management of patients with porphyria.