American Journal of Medical Genetics 28:759-760 (1987)

Letter to the Editor: Krabbe Disease and Protruding Ears To the Editor:

Krabbe disease (globoid cell leukodystrophy) is a rapidly progressive degenerative disease of the nervous system [Suzuki and Suzuki, 19831. The most common form is the infantile type with onset between 3 and 6 months; regression of psychomotor development appears early, and death occurs before age 2 years. Krabbe disease is as an autosomal recessive disorder due to deficiency of galactocerebrosidase.

The disease is rare; however, over the last years we have seen nine affected children. In all of them the diagnosis was confirmed enzymatically. All children were of Arab origin: four were from different related Druze families, three were from related Muslim families, and the other two children were from different unrelated families. We noted protruding ears in two of the affected children (Fig. 1) and therefore decided to look prospectively for this particular sign in all affected children and their parents. Among five affected children examined prospectively, protruding ears were found in four: all the parents had normal ears. In the last family examined, the parents had noted themselves that the affected child and his brother, who died of the same disease, had protruding ears while the unaffected children had normal ears. We did not notice a particular segregation of this sign among the different families.

Fig. 1. Protruding ear in one of the children affected with Krabbe disease.

760 Zlotogora and Cohen

Protruding ears may be found in normal individuals and sometimes are familial; they have also been described in several syndromes [Smith, 19821. Smith and Takashima [ 19781 demonstrated that protruding ears are usually associated with a defect in development or function of the posterior auricular muscle and that it may be one of the manifestations of neuromuscular diseases or disorders with central nervous system dysfunction. We did not find protruding ears among patients with other neurodegenerative disorders; it may be that this represents an early symptom of central nervous system dysfunction that is found only in Krabbe disease, since the onset of the symptoms is particularly early in this disease.

REFERENCES

Smith DW (1982): “Recognizable Patterns of Human Malformation.” Philadelphia: WB Saunders Co. Smith DW, Takashima H (1978): Protruding auricle: A neuromuscular sign. Lancet 1:747-749. Suzuki K, Suzuki Y (1 983): Galactosylceramide lipidosis; globoid cell leukodystrophy (Krabbe‘s disease). In

Stanbury JB, Wyngaarden JB, Fredrickson DS, Goldstein JL, Brown MS (eds): “The Metabolic Basis of Inherited Disease,” 5th Ed. New York: McGraw Hill, pp 857-880.

Joel Zlotogora Tirza Cohen Department of Human Genetics Hadassah Medical Center The Hebrew University Jerusalem, Israel

Edited by John M. Opitz and James F. Reynolds

NOTE ADDED IN PROOF

Two additional children affected with Krabbe disease were recently diagnosed; in both protruding ears were found.