ABSTRACT
BACKGROUND: An unexpectedly detected prolonged activated partial thromboplastin time (APTT) can be a harmless laboratory finding, but can also reflect a thrombotic tendency or a bleeding disorder. The assistance of laboratory professionals in the interpretation of an unexpectedly detected prolonged APTT (uAPTT) is often required. The way in which uAPTTs are evaluated in laboratories was assessed in this international study with the aim of determining whether laboratory professionals are able to fulfill this need. METHODS: Postanalytical practices after uAPTT were investigated and the mixing study methodology (if used) was studied by circulating a case report with a questionnaire to staff in the invited laboratories. In addition, the interpretations of those staff regarding the presence or absence of inhibitors in three APTT mixing study scenarios were examined. RESULTS: Large within- and between-country variations were detected in both postanalytical practices and mixing study methodologies among the 990 responding laboratories, 90% of which were in 13 countries. Shortcomings regarding the investigation of uAPTTs leading to potentially incorrect or delayed clinical diagnoses were found in 88% of the laboratories. Of the laboratories to which the interpretative questions were sent, 49% interpreted all mixing study scenarios correctly. uAPTTs were investigated appropriately and all mixing study scenarios interpreted correctly in parallel in only 9.6% of the participating laboratories. CONCLUSIONS: The clinical requirement for the assistance of laboratory professionals in the interpretation of uAPTTs cannot be met at most of the participating laboratories. Laboratory professionals should be trained in the evaluation of ordinary laboratory tests, such as that for uAPTTs.
Subject(s)
Blood Coagulation Tests/methods , Medical Laboratory Personnel , Partial Thromboplastin Time/methods , Child , Female , Humans , International Cooperation , Partial Thromboplastin Time/trends , Professional Competence , Reproducibility of Results , Surveys and QuestionnairesABSTRACT
La hemofilia A adquirida (HAA) posparto es una entidad extremadamente infrecuente (100 casos descritos en la literatura) y potencialmente grave. Se caracteriza por la aparición de anticuerpos antifactor viii (FVIII) circulante, que producen clínica hemorrágica en el puerperio, sin afectar al feto. Por lo general, los anticuerpos desaparecen espontáneamente en las primeras semanas o meses y no se reproduce en gestaciones posteriores. Pese a que el retraso en el diagnóstico puede ser fatal, la HAA posparto presenta buena respuesta al tratamiento procoagulante e inmunosupresor, siendo de mejor pronóstico que otras causas de hemofilia A. Por esta razón, ante síntomas como metrorragia incoercible sin causa obstétrica que lo justifique y signos como pruebas de coagulación alteradas, debemos sospechar esta enfermedad y realizar las pruebas diagnósticas de confirmación para instaurar sin demora el tratamiento sintomático y etiológico (AU)
Postpartum acquired hemophilia A is an extremely rare (100 cases in the literature) and potentially serious disease. Anti-circulating factor viii (FVIII) antibodies develop in the puerperium, leading to hemorrhagic symptoms without fetal danger. In general, the antibodies disappear spontaneously in the first few weeks or months after delivery and do not recur in subsequent pregnancies. Even though a delay in diagnosis can be fatal, postpartum hemophilia A has a good response to treatment and a better prognosis than other causes of hemophilia A. Consequently, it is important to suspect this disease in the presence of symptoms such as intractable vaginal bleeding without underlying obstetric disorders and signs such as abnormal coagulation tests. The correct diagnostic tests must be carried out to establish symptomatic and etiologic treatment without delay (AU)
