Significance of increased blastic-appearing cells in bone marrow following myeloablative unrelated cord blood transplantation in adult patients.

An abnormal increase of nonleukemic blastic-appearing lymphocytes in bone marrow (BM) specimens has been reported after unrelated cord blood transplantation (UCBT). This study analyzed the incidence, chronology, biological features, and clinical significance of elevated numbers of these cells in a series of 165 consecutive adult patients demonstrating myeloid engraftment after myeloablative UCBT in a single institution. The patients' BM samples were routinely evaluated by cytomorphology at different time points after UCBT. When ≥5% of blastic-appearing cells were detected by cytomorphology in the BM, samples were also evaluated by multiparametric flow cytometry to characterize these cells. Systematic chimerism analyses of BM samples using PCR amplification of short tandem repeat markers were performed. Forty-three patients (cumulative incidence, 26.1%) demonstrated ≥5% of nonmalignant blastic-appearing cells in BM after a median of 101 days after UCBT (range, 28-377 days). All of these patients had full-donor chimerism and a clinical course without leukemic relapse. Multiparametric flow cytometry analyses performed in 36 of the 43 patients showed a polyclonal expansion of B lymphocytes with a broad spectrum of maturation stages. An increased number of nonmalignant blastic-appearing cells was significantly associated with a high number of lymphocytes infused at the time of UCBT and with low rates of acute and chronic extensive graft-versus-host disease, suggesting a potential immunoregulatory role of these cells. The observation of ≥5% nonmalignant blastic-appearing cells in BM samples after myeloablative UCBT is frequent, and these should be distinguished from malignant blasts.

Contrast-enhanced power Doppler ultrasound in the diagnosis and follow-up of inflammatory abdominal masses in Crohn's disease.

OBJECTIVE: The purpose of this study was to evaluate the potential usefulness of contrast-enhanced power Doppler ultrasound in the detection and follow-up of local complications (phlegmon and abscess) in Crohn's disease. METHODS: With this aim, 28 patients with suspected abdominal inflammatory mass were examined with power Doppler ultrasound before and after intravenous administration of the ultrasound contrast agent Levovist, with evaluation of vascularity within and/or around the inflammatory mass. Colour Doppler flow was characterized as clearly visible, minimally visible or absent. All the patients underwent a post-contrast computed tomography exam. RESULTS: Power Doppler ultrasound, after administration of contrast medium, allows the detection of small inflammatory masses in Crohn's disease, particularly those under 2 cm in diameter, when compared with computed tomography. CONCLUSIONS: We conclude that contrast-enhanced power Doppler ultrasound is a sensitive method for the detection of small abdominal inflammatory masses and for differential diagnosis between phlegmon and abscess.