Familial periodic paralysis

Oral Treatment of hypokalemia in the following conditions With or without metabolic alkalosis digitalis intoxication familial periodic paralysis diabetic acidosis diarrhea and vomiting surgical conditions accompanied by nitrogen loss, vomiting, suction drainage, diarrhea, and increased urinary excretion of potassium certain cases of uremia hyperadrenalism starvation and debilitation corticosteroid or diuretic therapy. 

Special risk Use with caution in the presence of cardiac disease, particularly in digitalized patients or in the presence of renal disease, metabolic acidosis, Addison disease, acute dehydration, prolonged or severe diarrhea, familial periodic paralysis, hypoadrenalism, hyperkalemia, hyponatremia, and myotonia congenita. 

Schott GD, McArdle B. 1974. Barium-induced skeletal muscle paralysis in the rat, and its relation to human familial periodic paralysis. J Neurol Neurosurg Psychiatr 37 32-39. 

With prolonged use of the carbonic anhydrase Inhibitor diuretics, the urine becomes more alkaline, and the blood becomes more acidic. When acidosis occurs, the carbonic anhydrase Inhibitors lose their effectiveness as diuretics. They remain Ineffective until normal acid-base balance In the body has been regained. For this reason, this class of compounds Is limited In Its diuretic use. Today, they are most commonly used In the treatment of glaucoma. In which they reduce the rate of aqueous humor formation and, subsequently, reduce the Intraocular pressure. These compounds also have found some limited use In the treatment of absence seizures, to alkallnize the urine, to treat familial periodic paralysis, to reduce metabolic alkalosis, and prophylactically, to reduce acute mountain sickness. 

Glucose-6-phosphate dehydrogenase deficiency (6) Myoglobinuria (13), familial periodic paralysis (14) Sickle cell anemia (15)... 

McDowell, M. K., Herman, R. H., and Davis, T. E., 1963, The effect of a high and low sodium diet in a patient with familial periodic paralysis. Metabolism 12 388. 

Cannon SC, Strittmatter SM 1993 Functional expression of sodium channel mutations identified in families with periodic paralysis. Neuron 10 317—326... 

Fontaine B, Vale-Santos J, Jurkat-Rott K et al 1994 Mapping of the hypokalaemic periodic paralysis (HypoPP) locus to chromosome lq31-32 in three European families. Nat Genet 6 267-272... 

Ptacek Again, those are pretty rare. The patients are thyrotoxic and they have paralysis just like the hypokalaemics, except that when you ablate their thyroid, the thyrotoxic periodic paralysis resolves. There was one small family reported. I believe that this is a hereditary disorder, but we don t see it as a hereditary disorder much because it is a predisposing mutation and you also have to be thyrotoxic for the paralysis to manifest. We ve looked for Ca channel mutations in those patients but haven t found any. 

Ptacek The one thing that is different is that their K levels tend to be much lower. The familial hypokalaemic patients would typically have a K+level of2.1—3.2 during an attack. If I see a patient that has a l< level of 1.7—1.9 (which is alarmingly low), the first thing I think of is thyrotoxic periodic paralysis, because they tend to be really low. I don t know precisely why this is the case. 

The genetic defect knoivn as hyperkalemic periodic familial paralysis" causes skeletal paralysis and hyperkalemia. In this disease, only one of the sodium channels is abnormal, and it has been suggested that a disease in ivhich all the sodium channels were affected would be nonviable (Peterson 1997). 

One problem in this category which deservedly received world-wide attention was the neurological illness which affected fishermen and their families around Minamata Bay in Southern Japan in the period, 1953-61, and subsequently in freshwater at Niigata in 1965. The syn toms of what came to be known as Minamata disease were tragic [397] and included muscular weakness, blindness, inco-ordination, paralysis and in some cases, coma and death. The onset of the disorder coincided with large-scale mortalities in fish in the bay and local sea-birds and household cats were also affected. The cause was eventually discovered to be the presence of high levels of methyl mercury in the fish. 

Dalakas MC, Engel WK. (1983) Treatment of "permanent" muscle weakness in familial hypokalemic periodic paralysis. Muscle Nerve 6, 182-186. 

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