[Hereditary angioedema. Diagnostic and treatment errors as systemic lupus erythematosus]

Symptoms of hereditary angioedema are intermittent edema of subcutaneous tissues, abdominal organs, upper airways, and brain. Because of spontaneous mutation, in 20% of patients a familial history is lacking. Serological hallmarks are diminished complement factor 4 and C1-esterase inhibitor. The heterogenicity of the clinical symptoms frequently leads to false or delayed diagnosis.

We report on a 50-year-old male patient with intermittent joint swellings, abdominal complaints, pleural effusions, ascites and headaches with disturbances of consciousness since early adulthood. Diagnosis was systemic lupus erythematosus. Immunosuppressive therapy was ineffective over months. Careful re-evaluation of the patient's clinical history and further laboratory examinations led to the diagnosis of an hereditary angioedema. Anamnestic and laboratory exploration of family members disclosed four other cases. Two of them also were symptomatic for decades without adequate diagnosis.

In case of intermittent swellings, abdominal complaints, laryngeal edema, pleural effusions or ascites, differential diagnosis should involve hereditary angioedema. With early diagnosis and adequate treatment, prognosis is good. Since ACE inhibitors can aggravate the disease they are contraindicated. Diagnosis, pathogenesis, and treatment are discussed by reviewing the literature.