Background: Trisomies 13 and 18 (T13/18) are autosomal trisomy syndromes with dismal prognoses. Deciding whether to perform a chromosomal analysis for the definitive diagnosis is often difficult (even for experienced pediatricians) because representative clinical signs may not be found in all T13/18 neonates.
Objectives: This study aimed to investigate any clinical signs that could be useful for screening for T13/18 in participants without the representative clinical signs traditionally found in odd-looking neonates with malformation syndromes.
Patients and methods: We retrospectively analyzed 15 T13/18 patients, 33 trisomy 21 patients, and 48 controls with other malformation syndromes, for apparent clinical signs during the neonatal period. All participants had been admitted to the neonatal intensive care unit of Kansai Medical University over a nine-year period.
Results: The three leading clinical signs in patients with T13/18 were congenital heart diseases (CHD; 100%), low-set ears (LSE; 80%), and intrauterine growth restriction (IUGR; 73.3%). A comorbidity of these two leading non-specific clinical signs was CHD with LSE, which showed the highest diagnostic accuracy between T13/18 and controls with a sensitivity of 80.0% and a negative predictive value of 92.5%. The chi-square test among these three groups (P < 0.01) and multiple comparison tests of proportional differences showed that the comorbidity of CHD with LSE was specific for autosomal trisomy syndromes. A comorbidity of CHD with IUGR also revealed a similar diagnostic accuracy with a sensitivity of 73.3% and a negative predictive value of 90.9% as well as a specificity for T13/18.
Conclusions: The comorbidities of either CHD with LSE or CHD with IUGR should be suspected in neonates with autosomal trisomy syndromes, particularly T13/18 without the expected representative clinical signs.
Keywords: Comorbidity; Congenital Heart Diseases; Intrauterine Growth Restriction; Low-Set Ears; Neonate; Trisomy 13; Trisomy 18.