123P The difficult path to diagnosis of the patient with spinal muscular atrophy

Abstract

News treatments make early diagnosis of spinal muscular atrophy (SMA) critical. The objective of this study is to analyse the different factors that influence delay in diagnosis. Patients with a molecular diagnosis of types I, II, and III SMA were included. Several parameters were studied, such as age at onset of first sign, what sign it was, and the time from recognition of first sign to confirmed diagnosis. Neurologists specialized in SMA conducted interviews, supported by the review of medical records when deemed necessary. A total of 112 patients were interviewed. SMA I n = 40, SMA II n = 48, SMA III n = 24. The median age in months at the time of reporting the first sign was SMA I: 1.5 (R: 0–7), SMA II: 9 (R: 2–20), SMA III: 18 (R: 8–180). In all subtypes, first signs were identified by parents from 75% to 85% of the times. The top-3 detected signs were: SMA I: hypotonia (38.5%), developmental delay (33.3%), feeding difficulties (17.9%); SMA II: inability to stand (23%), inability to walk unaided (23%), proximal weakness (23%); SMA III: frequent falls (50%), unsteady gait (20.8%), developmental delay (16.7%). The median time from first sign to first medical consultation was less than a month in all 3 types. The SMN genetic study was requested by the healthcare professional during the first consultation in 22.5% of SMA I patients, 16.7% of SMA II patients and in none of the SMA III patients. The median time in months, from first sign to confirmed molecular diagnosis in SMA I was: 2 (R: 0–11), in SMA II: 10 (R: 3–46), in SMA III: 31.5 (R: 4–288). There is a significant delay in SMA diagnosis mainly related to the absence of clinical suspicion. The delay is shorter in SMA I and longer in SMA III. Other factors include deficiencies in the health care system.