La sindrome di Jervell e Lange Nielsen : revisione della letteratura con approfondimento di un caso

Jervell and Lange-Nielsen (1975) first described a syndrome characterized by congenital nerve deafness, prolongation of the QT interval in the ECG, syncopal attacks and sudden death. An important difference between this syndrome and the syndrome described by Romano-Ward (episodes of unconsciousness, also sudden death in some cases and furthermore prolongation of QT) is the congenital deafness which is not found in the cases described by Romano-Ward. The cause of fainting and the reasons for the prolongation of the QT interval have been exhaustively discussed: no definite explanation has been found. The condition was supposed to be due to an inborn error of myocardial metabolism, caused by some unknown enzymatic deficiency. Abnormalities of the T waves themselves have also been observed and include large, bifid or inverted form. The long QT interval causes an abnormally long vulnerable period, enhancing the possibility that ectopic beats will trigger a ventricular dysrhythmia and attacks of syncope provoked by exertion or mental stress. The resemblance to attacks of angina pectoris is obvious but are certainly not caused by coronary ischemia. In treating syncopal attacks of this syndrome, several drugs should theoretically be of value: digitalis to shorten the QT interval, a beta-receptor blocking agent to reduce adrenergic hyperactivity, and a sedative to control emotional hyperreaction. Several Authors have discussed the genetic problems; they find a high frequency of consanguineous unions among the parents of affected children, and they conclude that the data are consistent with a hypothesis of recessive inheritance. Those heterozygous for the gene may have slight or moderate prolongation of the QT interval. Anaemia has been observed in many patients with this syndrome. This anaemia was hypochromic, microcytic, and other laboratory findings were also consistent with iron deficiency anaemia. The main clinical features shown by a case of Jervell and Lange-Nielsen syndrome are described in this paper.

Nel 1957 Jervell e Lange Nielsen per primi descrissero una sindrome caraterizzata da sordità neurosensoriuale congenita, allungamento del tratto QT dell'ECG, attacchi sincopali e morte improvvisa. La causa dei disturbi cardiaci può essere ricondotta ad un difetto congenito nel metabilsmo cardiaco, probabilmente riconducibile ad una deficienza enzimatica. Sono state descritte inoltre anomalie dell'onda T. Lo stress mentale o fisico sembra favorire l'insorgenza dell'aritmia e degli attacchi sincopali. Per qunto concerne il trattamento farmacologico, diverse sortanze sono state impegate con alterna fortuna: la digitale, i betabloccanti ed i sedativi. Da un punto di vista genetico, i dati frequentemente riportati di matrimonni tra consangunei nelle famiglie con bambini affetti da tale sindrome, ha rafforzarto l'ipotesi che la trasmissione avvenga in modo autosomico recessivo. Anche un'anemia ipocromica sembra eesere delle caratteristiche più frequentemente correlate alla sindrome di Jervell e Lange Nielsen. In questo lavoro sono riportati i dati clinici salienti di un bambino giunto alla nostra osservazione.