PAS-positive lymphocyte vacuoles can be used as diagnostic screening test for Pompe disease

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

Clinicopathological Analysis of Hematological Disorders in Tube-Fed Patients with Copper Deficiency

Object Anemia and leukopenia caused by copper deficiency are well-documented consequences of long-term total parenteral nutrition. We measured the serum copper levels of bed-ridden patients receiving enteral feeding, and evaluated optical and ultrastructural features of bone marrow before and after copper supplementation.Patients and Methods Serum samples were obtained from 15 bed-ridden elderly patients receiving tube feeding (TF) and 10 age-matched bed-ridden patients who took food orally (CO), and the copper ceruloplasmin concentration of each sample was measured. Bone marrow samples were obtained from patients who exhibited copper deficiency and leukopenia and/or anemia before and after the copper supplementation, for use in light and electron microscopic analysis.Results The tube-fed patients had significantly lower mean serum copper and ceruloplasmin concentrations than the control patients. Seven of the 15 tube-fed patients had reduced serum copper concentrations and leukopenia. Six of those 7 patients also had anemia. Copper sulfate was administered to those 7 patients by enteral tube;their copper concentration, anemia and leukopenia improved within 1 month after they were administered copper sulfate. In the bone marrow examination before copper supplementation, light microscopy showed cytoplasmic vacuolization in both myeloid and erythroid precursors, and electron microscopy showed electron-dense deposits in mitochondria and cytoplasm of erythroid and myeloid cells. After copper supplementation, these pathological changes disappeared.Conclusions Bicytopenia is likely to occur in tube-fed patients with copper deficiency. Copper deficiency appears to be associated with cytoplasmic vacuolization and electron-dense deposits in mitochondria in erythroid and myeloid cells