Acceleration of diabetic wound healing with adipose-derived stem cells, endothelial-differentiated stem cells, and topical conditioned medium therapy in a swine model.

OBJECTIVE: The purpose of our study was to investigate the effect of adipose-derived stem cells (ASCs), endothelial-differentiated ASCs (EC/ASCs), and various conditioned media (CM) on wound healing in a diabetic swine model. We hypothesized that ASC-based therapies would accelerate wound healing. METHODS: Diabetes was induced in four Yorkshire swine through intravenous injection of streptozotocin. ASCs were harvested from flank fat and cultured in either M199 or EGM-2 medium. A duplicate series of seven full-thickness dorsal wounds were surgically created on each swine. The wounds in the cellular treatment group underwent injection of low-dose or high-dose ASCs or EC/ASCs on day 0, with a repeat injection of one half of the initial dose on day 15. Wounds assigned to the topical CM therapy were covered with 2 mL of either serum-free M199 primed by ASCs or human umbilical vein endothelial cells every 3 days. Wounds were assessed at day 0, 10, 15, 20, and 28. The swine were sacrificed on day 28. ImageJ software was used to evaluate the percentage of wound healing. The wounded skin underwent histologic, reverse transcription polymerase chain reaction, and enzyme-linked immunosorbent assay examinations to evaluate markers of angiogenesis and inflammation. RESULTS: We found an increase in the percentage of wound closure rates in cell-based treatments and topical therapies at various points compared with the untreated control wounds (P < .05). The results from the histologic, messenger RNA, and protein analyses suggested the treated wounds displayed increased angiogenesis and a diminished inflammatory response. CONCLUSIONS: Cellular therapy with ASCs, EC/ASCs, and topical CM accelerated diabetic wound healing in the swine model. Enhanced angiogenesis and immunomodulation might be key contributors to this process.

Platelet refractoriness in acquired hemophagocytic syndrome.

BACKGROUND: Acquired hemophagocytic syndrome (AHPS) is a severe inflammatory disorder often caused by Epstein-Barr virus (EBV). Proliferation of activated macrophages produces uncontrolled cytokine production. Thrombocytopenia is common in AHPS, previously attributed to inadequate or ineffective marrow platelet (PLT) production. PLT transfusion response is not well reported. Two patients with fatal AHPS developed unexplained PLT transfusion refractoriness before definitive diagnosis. CASE REPORTS: PLT refractoriness was noted during the care of two patients. The refractoriness was determined to be nonimmune and both demonstrated various clinical signs and laboratory findings consistent with AHPS. The first patient's AHPS was attributable to EBV infection. In the other patient, no underlying cause could be found. Both patients had an aggressive clinical course and succumbed to this relatively rare syndrome. The PLT refractoriness was evident before the AHPS diagnosis was made. DISCUSSION: AHPS is not generally a consideration in the evaluation of nonimmune PLT refractoriness. However, these illustrative cases make an argument for its consideration in the differential diagnosis of PLT refractoriness in severely ill patients. Once present, it is unclear if the refractoriness can be reversed by AHPS-targeted therapy.

Does routine repeat testing of critical values offer any advantage over single testing?

CONTEXT: Before being communicated to the caregiver, critical laboratory values are verified by repeat testing to ensure their accuracy and to avoid reporting false or erroneous results. OBJECTIVE: To determine whether 2 testing runs offered any advantage over a single testing run in ensuring accuracy or in avoiding the reporting of false or erroneous results. DESIGN: Within the hematology laboratory, 5 tests were selected: hemoglobin level, white blood cell count, platelet count, prothrombin time, and activated partial thromboplastin time. A minimum of 500 consecutive critical laboratory test values were collected retrospectively for each test category. The absolute value and the percentage of change between the 2 testing runs for each critical value were calculated and averaged for each test category and then compared with our laboratory's preset, acceptable tolerance limits for reruns. RESULTS: The mean results obtained for the absolute value and the percentage of change between the testing runs were 0.08 g/dL (1.4%) for hemoglobin levels, 50 cells/µL (10.2%) for white blood cell counts, 1500 cells/µL (9.9%) for platelet counts, 0.7 seconds (1.4%) for prothrombin time, and 5.1 seconds (4.4%) for activated partial thromboplastin time (all within our laboratory's acceptable tolerance limits for reruns). The percentage of specimens with an absolute value or a mean percentage of change outside our laboratory's acceptable tolerance limits for reruns ranged between 0% and 2.2% among the test categories. No false or erroneous results were identified between the 2 testing runs in any category. CONCLUSIONS: Routine, repeat testing of critical hemoglobin level, platelet count, white blood cell count, prothrombin time, and activated partial thromboplastin time results did not offer any advantage over a single run.