ABSTRACT
BACKGROUND: Thyrotoxic periodic paralysis (TPP) is characterized by episodes of neuromuscular weakness occurring in the context of hypokalemia and hyperthyroidism and has been predominantly described in Oriental populations. Whereas it is uncommon in Caucasians and Blacks, TPP does occur in individuals of Native American descent. The objective was to analyze the clinical, biochemical, and HLA characteristics of a group of Mexican mestizo patients with TPP. METHODS: The sample was comprised of 14 men with TPP diagnosed since January 1990, based on one or more episodes of flaccid paralysis, accompanied by hypokalemia and occurring in the context of clinical and biochemical hyperthyroidism. Eight were available for HLA testing. RESULTS: Hyperthyroidism was diagnosed before the development of periodic paralysis in five of the patients, whereas in six it occurred afterward. The severity of paralysis did not correlate with the degree of either hypokalemia or hyperthyroidism. An increased frequency of HLA-DR3 was found in Graves' patients without paralysis but not in those with paralysis, as compared to the general population. CONCLUSIONS: TPP is more common than previously thought in Mexicans, in whom it behaves as in other Native American groups. The lack of HLA-DR3 association in Graves' patients with TPP is interesting, but at the moment has no pathophysiological implications.
Subject(s)
Ethnicity , Graves Disease/complications , HLA Antigens/analysis , Hypokalemia/ethnology , Paralysis/ethnology , Thyrotoxicosis/ethnology , Adult , Asian People/genetics , Ethnicity/genetics , Gene Frequency , Genetic Predisposition to Disease , Graves Disease/blood , Graves Disease/immunology , HLA Antigens/genetics , HLA-DR3 Antigen/analysis , HLA-DR3 Antigen/genetics , Humans , Hypokalemia/blood , Hypokalemia/etiology , Hypokalemia/immunology , Indians, North American/genetics , Male , Mexico/epidemiology , Middle Aged , Paralysis/blood , Paralysis/etiology , Paralysis/immunology , Periodicity , Potassium/blood , Sex Factors , Spain/ethnology , Thyroid Hormones/blood , Thyrotoxicosis/blood , Thyrotoxicosis/etiology , Thyrotoxicosis/immunology , White People/geneticsABSTRACT
We describe a 54-year-old man who suffered from familial Mediterranean fever, but the fever has been the only symptom during a 10-year period. During this period, results of laboratory tests and roentgenographic studies were negative. On the basis of these findings we propose that familial Mediterranean fever can be included in the causes of persistent fever in patients with long periods of fever.
