Hereditary seizure

Methionine synthase deficiency (cobalamin-E disease) produces homocystinuria without methylmalonic aciduria 677 Cobalamin-c disease remethylation of homocysteine to methionine also requires an activated form of vitamin B12 677 Hereditary folate malabsorption presents with megaloblastic anemia, seizures and neurological deterioration 678... 

Hereditary folate malabsorption presents with megaloblastic anemia, seizures and neurological deterioration. 

The clinical symptoms of mitochondrial diseases are highly varied and include seizures, vomiting, deafness, dementia, stroke-like episodes, and short stature. Although there are many types of mitochondrial disorders, four of the most common types are as follows Kearns-Sayre syndrome, Leber s hereditary optic atrophy, MELAS (mitochondrial encephalopathy, lactic acidosis and stroke-like episodes) and MERRE (myoclonic epilepsy with ragged red fibres). 

Lactic acidosis is also caused by (1) drugs and toxins, such as ethanol, methanol, biguanides, isoniazid (see previous discussion), and streptozotocin (2) acquired and hereditary defects in enzymes involved in gluconeogenesis (3) disorders such as severe acidosis, uremia, liver failure, tumors, and seizures (4) anesthesia and (5) abnormal intestinal bacteria producing n-lactate (described in Chapter 25). 

Hereditary sulfite oxidase deficiency can occur alone or with xanthine oxidase deficiency. Both enzymes contain molybdenum (Chapter 27). Patients with sulfite oxidase deficiency exhibit mental retardation, major motor seizures, cerebral atrophy, and lens dislocation. Dietary deficiency of molybdenum (Chapter 37) can cause deficient activity of sulfite and xanthine oxidases. 

Evidence in mice indicates that the fetus may be particularly susceptible to compromised immunocompetence due to altered stem cell populations of key immunoactive cells (Barnett et al. 1990a, 1990b). Infants may be unusually susceptible to a chronic seizure disorder following exposure to chlordane, particularly if they have a hereditary predisposition, such as a positive familial history of febrile convulsions (Bernad 1989). 

Deficient la-hydroxylase activity, characterized by the infantile onset of severe hypocalcemia, moderate hypophosphatemia, and responsiveness to pltysiologic doses of calcitriol, has been called hereditary pseudo-vitamin D deficiency rickets (PDDR), vitamin D dependency because of its responsiveness to active vitamin D, or vitamin D-dependent rickets type 1. This disease is now more simply and appropriately termed vitamin D la-hydroxylase deficiency. Affected persons are normal at birth but have growth retardation, poor motor development, arrd generalized muscle weakness by 2 years of age. Affected children develop hypocalcerrria, hypophosphatemia, increased seram alkaline phosphatase activity, and increased seram PTH some develop hypocalcerrric seizures. Serum concentratiorrs of 1,25(0H)2D are low despite normal concerrtra-tions of 250HD responses to administration of 1,25(0H)2D are excellent. 

Patients with maple syrup urine disease are mentally retarded, have seizures, and show abnormal electroen-cephalographic patterns. The disease is probably hereditary, but the exact mechanism of transmission is not established. Although the pathogenesis of maple syrup urine disease is still unknown, the metabolism of the branched amino acids provides the key to understanding the proposed mechanism [97]. 

The three autosomal dominant diseases, acute intermittent porphyria (31.2) [1, 4], variegate porphyria (31.6) and hereditary coproporphyria (31.5) share a common symptomatology (Tables 31.3.1/31.3.2). Affected individuals suffer from acute attacks of severe, colicky, abdominal pain, mostly of several days duration and combined with nausea, vomiting, obstipation and subileus. Tachycardia and hypertension is often present too. Within a few days these symptoms may spontaneously subside or they may progress as well to a predominant motor neuropathy, disturbance of electrolyte balance (hyponatremia, hypomagnesemia), seizures, confusion and coma. 

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