Neuropathic pain in a patient with porphyria. Case report.

OBJECTIVE

Porphyrias represent a group of inherited or acquired disorders that involve enzymes that participate in heme synthesis. Acute manifestations affect the nervous system resulting in abdominal pain, vomiting, acute neuropathy, seizures, and mental disorders. The physiopathogeny results from the toxic effects of porphyrin precursors, and it can be triggered by drugs used routinely in medical practice, severe carbohydrate restriction, and metabolic stress. The objective of this report was to present the case of a late onset porphyria evolving to chronic pain.

METHODS

This is a 27 years old female who was admitted 5 months prior to her clinic appointment with severe abdominal pain without diagnosis. An exploratory laparotomy was indicated, which failed to demonstrate a cause for her pain. The patient was exposed to surgical trauma and drugs that can trigger porphyria, such as ketoprophen, metoclopramide, and antibiotics, and she evolved with significant hyponatremia, increased liver enzymes, seizures, and loss of movements that led to be admitted to the Intensive Care Unit. After the diagnosis of porphyria was made, the patient remained with pain in the lower limbs, being referred to the Pain Department of Santa Casa de Misericórdia de São Paulo. Treatment with amitriptyline, gabapentin, opioid, and simple analgesics was instituted; however, the patient continued to present recurring episodes of porphyria and, feeling insecure with the conduction of the case, she stopped the treatment.

CONCLUSIONS

Porphyria is one of the rare groups of enzymatic disorders that remain unknown by the great majority of health professionals. Upon recognizing this lack of knowledge about the disease, the level of stress and insecurity of the patient increases hindering adhesion to and continuity of the treatment.