Low immature platelet fraction suggests decreased megakaryopoiesis in neonates with sepsis or necrotizing enterocolitis.

OBJECTIVE: In order to conclude on the megakaryopoietic activity during thrombocytopenia in sepsis or necrotizing enterocolitis (NEC), we analyzed the immature platelet fraction (IPF). STUDY DESIGN: Serial measurements of platelet counts and IPF in neonates with blood culture-proven late-onset sepsis (n=21) or surgical NEC (n=12) at T0: prior to the diagnosis of sepsis/NEC; T1: at diagnosis; T2: days 3 to 5 after onset; T3: days 8 to 12 after onset. RESULT: In parallel to declining platelet counts, the median absolute IPF significantly decreased between T0 and T2 in neonates with sepsis or NEC. We found a significant positive correlation between the platelet count and absolute IPF (r=0.71; P<0.001). In patients with low IPF (<2 per nl), the platelet count did not subsequently increase. Neonates with NEC who died exhibited significantly lower IPF compared with survivors (P<0.05). CONCLUSION: Low absolute IPF values during the course of neonatal sepsis/NEC suggest suppression of megakaryopoietic activity.

In utero development of symmetric thalamic and brainstem necrosis in a preterm hydropic stillborn.

Focal and symmetric necrotic lesions of the brainstem are thought to result from fetal hypotension or cardiac arrest in the perinatal period and thus occur in the course of postnatal intensive care rather than in utero. Here, we report for the first time on brainstem necrosis in a preterm stillborn demonstrating that brainstem necrosis occurs already in utero. The preterm stillborn of 28 weeks gestation of a mother that suffered from HELLP-syndrome was severely affected by a fetal hydrops with bilateral pleural effusions and lung hypoplasia. Bilateral tegmental brainstem necrosis and thalamic lesions were detected.

Differentiation, proliferation and apoptosis in primary and recurrent primitive neuroectodermal tumors of childhood.

Primitive neuroectodermal tumors (PNETs) of the CNS are a group of embryonal tumors composed of small undifferentiated or poorly differentiated cells. Infratentorially located PNETs are a synonym for medulloblastomas. In this study 31 PNETs, including 5 recurrent tumors, were examined. All children underwent neurosurgery and chemotherapy according to the HIT and HIT-SKK protocols. The specimens were investigated both for their expression of nine immunohistochemical markers for neuronal, astrocytic, mesenchymal and epithelial differentiation and for their proliferation. Results regarding cellular differentiation were confirmed ultrastructurally. Apoptosis was detected by labeling the 3'OH ends generated by DNA fragmentation and by electron microscopy. Glial differentiation was shown to have a prognostic relevance, with an elevated (twofold) risk of recurrence. Neuronal differentiation also indicated a tendency to poor prognosis. Those tumors that recurred later showed an increased proliferation rate (69%) compared with nonrecurrent tumors (58%). Apoptosis was identified in all tumors examined. The proportion of apoptotic cells could not be related to the effect of therapy. These results indicate that cellular differentiation may be a useful predicative factor for the prognosis of cerebral PNETs.