Premium
PAS‐positive lymphocyte vacuoles can be used as diagnostic screening test for Pompe disease
Author(s) -
Hagemans Marloes L. C.,
Stigter Rolinda L.,
Capelle Carine I.,
Beek Nadine A. M. E.,
Winkel Leon P. F.,
Vliet Laura,
Hop Wim C. J.,
Reuser Arnold J. J.,
Beishuizen Auke,
Ploeg Ans T.
Publication year - 2010
Publication title -
journal of inherited metabolic disease
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.462
H-Index - 102
eISSN - 1573-2665
pISSN - 0141-8955
DOI - 10.1007/s10545-009-9027-4
Subject(s) - receiver operating characteristic , lymphocyte , medicine , glycogen storage disease type ii , cutoff , gastroenterology , vacuolization , peripheral blood lymphocyte , peripheral blood , pathology , disease , enzyme replacement therapy , physics , quantum mechanics
Screening of blood films for the presence of periodic acid‐Schiff (PAS)‐positive lymphocyte vacuoles is sometimes used to support the diagnosis of Pompe disease, but the actual diagnostic value is still unknown. We collected peripheral blood films from 65 untreated Pompe patients and 51 controls. Lymphocyte vacuolization was quantified using three methods: percentage vacuolated lymphocytes, percentage PAS‐positive lymphocytes, and a PAS score depending on staining intensity. Diagnostic accuracy of the tests was assessed using receiver operating characteristic (ROC) curves. All three methods fully discerned classic infantile patients from controls. The mean values of patients with milder forms of Pompe disease were significantly higher than those of controls, but full separation was not obtained. The area under the ROC curve was 0.98 for the percentage vacuolated lymphocytes (optimal cutoff value 3; sensitivity 91%, specificity 96%) and 0.99 for the percentage PAS‐positive lymphocytes and PAS score (optimal cutoff value 9; sensitivity 100%, specificity 98%). Our data indicate that PAS‐stained blood films can be used as a reliable screening tool to support a diagnosis of Pompe disease. The percentage of PAS‐positive lymphocytes is convenient for use in clinical practice but should always be interpreted in combination with other clinical and laboratory parameters.