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We present the first report of paternal transmission of congenital myotonic dystrophy (DM). The patients had typical congenital DM and showed unstable CTG repeats on Southern blot analysis. The mother had no expansion of the DM gene, but the asymptomatic father had minimal expansion of the CTG repeats.

The Mother and Infant with Myotonic Dystrophy Pregnancy and delivery present a number of risks for the mother suffering from myotonic dystrophy, and for her infant. Most of the time, she does not even know that she is affected by the disease and a carrier of the gene. We review the complications of pregnancy and delivery in myotonic patients, and propose a simple management with specific items for each gestational period. The child of a dystrophic mother has a 50% risk of inheriting the abnormal gene. He may also exhibit a developmental and malformation syndrome called "congenital myotonic dystrophy". From the beginning, he may show respiratory distress, thereafter inability to swallow and severely hypotonia. Later, he may demonstrate mental retardation. Some of the most obvious signs found in neonates in our practice are illustrated. We also add a few tests to the list of those already recommended for these children.

A clinical and genetic study of congenital myotonic dystrophy in Britain has been carried out in 70 patients from 54 sibships. The clinical aspects are analysed here, and the existence of a syndrome clinically distinct from myotonic dystrophy of later onset is confirmed. Characteristic features included neonatal hypotonia, motor and mental retardation, and facial diplegia. A high incidence of talipes occurs at birth together with hydramnios and reduced fetal movements during pregnancy, factors suggesting prenatal onset of the disorder in many cases. Prolonged survival is the rule after infancy, but the occurrence of numerous neonatal deaths in the sibships suggests the existence of unrecognized cases dying in the neonatal period.

Dysfunction of smooth muscles is not unusual in adults suffering from myotonic dystrophy but has not yet been reported in patients with the congenital form of the disease. Of two brothers, the younger one presented with the typical features of congenital myotonic dystrophy at birth. He developed severe constipation due to megacolon during his second year of life. In the older brother disturbances of gastrointestinal motility, causing repeated bouts of subileus during the newborn period, sprue-like symptoms during early childhood, and megacolon with constipation and incontinence later on, remained the only manifestation of myotonic dystrophy until the age of eight years when the diagnosis could be finally established by electromyography.

Undifferentiated type 2C fibers and satellite cells were increased in number in younger patients with congenital myotonic dystrophy (CMD) indicating immaturity in muscle fiber growth. The changes found in a 38-year-old man with CMD were identical to those described in late onset myotonic dystrophy. Type 1 fibers were found to become predominant with age. This suggests that in this disorder fiber type transformation progresses with age, presumably due to abnormal neural influences or aberrant sarcolemmal responses.

Congenital myotonic dystrophy HMD) is characterized by hypotonia, facies myopathica, feeding and respiratory problems, skeletal deformities and polyhydramniosis. It is an auto-somal-dominant disorder transmitted via the mother. The diagnosis can as a role be confirmed by examining the mother, but can fail as she might be asymptomatic. During a nine year period, eight children were diagnosed as CMD which means an incidence of one case per approximately 3500 live births. The diagnosis was confirmed in six of the mothers. The two floppy infants, where positive inheritance could not be proven, showed most of the signs and symptoms described in CMD. Four children died, two from respiratory insufficiency and two suddenly and unexpectedly. CMD may be one less common cause of sudden infant death syndrome (SIDS). The four children who survived displayed delayed psychomotor development.

The skeletal muscle in 3 preterm infants (27, 34, 37 weeks gestation age) born to mothers with myotonic dystrophy showed a syncytial pattern at 27 weeks and a decreasing percentage of satellite cells and central nuclei at 34 and 37 weeks gestation. The fiber type differentiation was observed only at 37 weeks of gestational age. In all 3 cases muscle fibers with multiple acid phosphatase positive sites were seen. The muscle spindles also had thick capsules and showed lack of morphologic and histochemical differentiation into fiber types. These findings suggest immaturity of skeletal muscle in comparison to the normal. The immaturity of the skeletal muscle correlated well with the prognosis of the patients.

Ultrasonography or computed tomography scanning of the brain was performed in 10 infants with congenital myotonic dystrophy between the age of 1 day and 2 months, and showed intracranial abnormalities in all. Ventricular dilation was diagnosed in eight (80%), subarachnoid hemorrhage in one, and white matter infarcts in one. The common finding of ventricular dilation is probably related to developmental brain abnormality dating back to fetal life, because it was already present in three infants scanned on the first day of life. Neonatal asphyxia was present in seven infants, associated with intraventricular hemorrhage in two. The relationship between these changes and mental retardation, which is a common feature in this disease, is unclear.

This work was supported by the VA Merit Review (support to T.A.). We thank Dr. Ana M. Tari for her suggestions in preparation of the manuscript.

Transverse colonic accounts for 2–4% of all forms of colonic volvulus and has its highest mortality rate (33) [1] , [2] , [3] . Only forty cases of pediatric transverse colonic volvulus have been reported in the literature to date [4] . We report on a 16-year-old female with congenital myotonic dystrophy who underwent operative repair for transverse colonic volvulus, the first reported case of these two entities in combination.

In a case of myotonic dystrophy, discovered during childhood, peristalsis of the esophagus has been found to be abnormal in spite of paucity of clinical signs. Anomalous motility of its upper part and significantly depressed pressure in the lower segment, as shown by manometry, have been correlated with radiological abnormalities.

Congenital myotonic dystrophy is a rare disorder with a reported incidence of six per 100,000. Although anaesthetic problems in adults with myotonic dystrophy are well recognised, anaesthesia for children with congenital myotonic dystrophy is rarely described in the literature

Myotonic dystrophy is a relatively common disorder. Since the clinical expression is highly variable, diagnosis is often made only after the birth of an infant with severe congenital myotonic dystrophy. Seven such cases are described. A history of obstetric complications was present in the six multiparous mothers. Neither the neonatal features nor the pregnancy complications are specific, but their combinations should suggest the diagnosis, which can be confirmed by neurologic evaluation of the infant's mother.

The muscle spindle in the preterm infants with congenital myotonic dystrophy consisted of numerous, unfused intrafusal fibers. These fibers showed immature myofilament arrangement at 27 weeks but had the nuclear arrangement of bag and chain type. The motor endings were very sparse while prominent sensory endings were seen. At 34–37 weeks, even though the muscle fibers were unfused, the nuclear bag and chain fibers could be differentiated by the presence and absence of M line. Immature motor endings were seen at this stage. In conclusion, the muscle spindle in the preterm infants is immature.

Several unusual diaphragmatic problems in the neonate are presented and a new potential complication of the negative pressure respirator is illustrated. The association of bilateral diaphragmatic eventrations with chromosome anomalies is emphasized. In our experience the appearance of the chest on frontal and lateral views is usually so characteristic that no further evaluation is required. The relationship between several neuromuscular disorders and diaphragmatic dysfunction is discussed. A case of congenital myotonic dystrophy with unilateral eventration is illustrated.

1. Ballermann B J, Brenner BM. Biologically active atrial peptides. J Clin Invest 1985;76:2041-8. 2. Wei Y, Rodi CP, Day ML, et al. Developmental changes in the rat atriopeptin hormonal system. J Clin Invest 1987; 79:1325-9. 3. Robillard JE, Nakamura KT, Varille VA, Andresen AA; Matherne GP, VanOrden DE. Ontogeny of the renal response to natriuretic peptide in sheep. Am J Physiol 1988;254 (Renal Fluid Electrolyte Physiology 23):F634-41. 4. Cheung CY, Gibbs DM, Brace RA. Atrial natriuretic factor in maternal and fetal sheep. Am J Physiol 1987;252:E27982. 5. Ross MG, Ervin MG, Lam RW, Castro L, Leake RD, Fisher DA. Plasma atrial natritiretic peptide response to volume expansion in the ovine fetus. Am J Obstet Gynecol 1987; 157:1292-7. 6. Tulassay T, Rascher W, Seyberth HW, Lang RE, Toth M, Sulyok E. Role of atrial natriuretic peptide in sodium homeostasis in premature infants. J PEDIATR 1986;109:1023-7. 7. Yamaji T, Hirai N, Ishibashi M, Takaku F, Yanaihara KT, Nakayama T. Atrial natriuretic peptide in umbilical cord blood: Evidence for a circulating hormone in human fetus. J Clin Endocrinol Metab 1986;63:1414-% 8. Weiner CP. Cordocentesis for diagnostic indications: Two years' experience. Obstet Gynecol 1987;70;6648. 9. Ballermann B J, Brenner BM. Role of atrial peptides in body fluid homeostasis. Circ Res 1986;58:619-30. 10. Lang RE, Tholken H, Ganten D, Luft DC, Ruskoaho H, Unger T. Atrial natriuretic factor: A circulatory hormone stimulated by volume loading. Nature 1985;314:264-6. 11. Garcia R, Debinski W, Gutkowska J, et al. Gluco and mineralocorticoids may regulate the natriuretic effects and the synthesis of and release of atrial natriuretie factor by the rat atria in vitro. Biochem Biophys Res Commun 1985; 131:806-14. 12. Brace RA, Cheung CY. Cardiovascular and fluid responses to atrial natriuretic factor in sheep fetus. Am J Physioi 1987;253:R561-7.

Genetic analysis of 54 sibships containing 70 patients with congenital myotonic dystrophy has shown paternal transmission in only one case, the disorder being maternally transmitted in 51 sibships. No instance of new mutation was found. At least half the sibs were unaffected; 9 sibs were affected without definite congenital involvement. No evidence for genetic heterogeneity was found, most affected mothers having few or no symptoms. There was no disturbance of sex ratio for the affected grandparents, nor in the sibships of the affected parents. The genetic data from this study and from previous published reports support the clinic evidence that the congenital form of myotonic dystrophy results from a maternal intrauterine factor affecting those individuals carrying the myotonic dystrophy gene.

Histopathology and histochemistry were studied in biopsied muscles from eight patients with the congenital form of myotonic dystrophy (congenital MyD) and one patient with the adult form (adult MyD). In the muscle pathology of the four patients aged between 5 and 11 years with congenital MyD, there was no immaturity of the fibers and the histological alterations were minimal. The pathological findings of the adult patient with congenital MyD resembled those of adult MyD. The immature condition of the musculature observed during the early infantile period, therefore, may once improve with motor development during childhood and, after that, the muscle fibers may degenerate in a similar manner to that seen in adult MyD. Two patients with marked talipes equinovarus displayed grouped atrophy. Small angular fibers and pyknotic nuclear clumps were observed in five patients. These findings suggest that some neurogenic factor might be involved in the muscular changes in this disorder.

• Histometric data on muscle fiber types were studied in two cases of congenital myotonic dystrophy (CMD); one underwent biopsy at the age of 5 months and the other at the age of 10 years. A previously unreported severe deficiency of type IIB fibers were found in both cases. In addition, in the first case, there was type I fiber preponderance and hypotrophy as described in cases of congenital fiber type disproportion (CFTD). It is suggested that an abnormality of motor unit maturation may be common to CMD and to CFTD, and that this results from a disorder of neural trophic influences during muscle development.

Two brothers with congenital myotonic dystrophy also had cystinuria with large renal stones. This report is the first to document the concurrence of cystinuria and congenital myotonic dystrophy. It is uncertain whether these two conditions are coincidental or share a common pathogenesis.

Ten infants with congenital myotonic dystrophy admitted to the Dept Pediatrics and Neonatal Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, 1982-86, were investigated by ultrasonography or CT brain scans between 1 day and 2 months of age.