Rare viral infections in children receiving hemopoietic stem cell transplant.

Viral infections are a rare complication in autologous hemopoietic stem cell transplant (HSCT) recipients but represent a frequent cause of disease after allogeneic HSCT. In the last years, there has been an increase in the number of viral diseases observed in these patients. This fact may be at least partially due to an improvement in diagnostic facilities, but the increasing number of transplant procedures and the more severe immunosuppression may also have played an important role.

Invasive mycoses in children receiving hemopoietic SCT.

Invasive mycoses represent a rare but severe complication following hemopoietic SCT (HSCT) in children. Their incidence is related to the type of donor, being higher after allogeneic transplant, especially from alternative donors. Moreover, the incidence of invasive mycoses varies in the different post transplant phases. Neutropenia, lymphopenia, GvHD, high-dose steroids or other immunosuppressive drugs represent well-known risk factors. The clinical features of invasive mycoses after HSCT in children are similar to those observed in adults, and the diagnostic tools, including Aspergillus galactomannan antigen detection, are feasible also in pediatrics. Mortality due to invasive mycoses after HSCT in children is high.

Bacteremias in children receiving hemopoietic SCT.

The incidence of bacteremia following hemopoietic SCT (HSCT) changes over time from the procedure. The first 30 days have the highest incidence, both in autologous and allogeneic HSCT recipients. In the following periods, bacteremia is a frequent complication in allogeneic HSCT, especially from alternative donors. Gram-positive cocci represent the most frequent cause of single-agent bacteremia. Knowledge of epidemiology (incidence and etiology) of bacteremias following HSCT is pivotal for planning management strategies (prevention, diagnosis and therapy) that must be distinct in the different post-transplant period.

Non-endocrine late complications in children after allogeneic haematopoietic SCT.

Non-endocrine events represent a heterogeneous group of complications occurring in children who survive long term after haematopoietic SCT. This review highlights the late sequel in a growing child. The preparative regimen itself with high-dose chemotherapy and/or radiotherapy (TBI) or the treatment given before the transplant procedure may cause organ damage with permanent sequel. Immune reconstitution and chronic GvHD have crucial role in occurrence of clinical abnormalities and late severe infections. Autoimmune syndromes may occur after use of novel transplant modalities (cord blood transplantation, reduced intensity conditioning regimen and haploidentical T-cell-depleted SCTs). Exposure to chemo- and/or radiotherapy increases the risk of second malignant neoplasms. Surveillance strategy focusing on each potential complication risk at continuous follow-up will allow vigilant post transplant care. Each paediatrician must be well versed in appropriate monitoring of these complications. Guidelines and recommendations are provided for serious problems occurring at follow-up, which must rapidly be identified so that appropriate intervention can be initiated. To achieve cure at a lowest possible price in terms of suffering and cost expenditures for health care is an extended frontier of paediatric haematopoietic SCT and biggest challenge for a paediatrician.

Prevention and treatment of acute GvHD.

GvHD remains a source of significant morbidity and mortality in the setting of allogeneic haematopoietic SCT. Improving outcomes in stem cell transplant recipients requires additional therapeutic modalities for GvHD, especially for patients who fail to respond to initial therapy with steroids. Moreover, while the absence of acute GvHD (aGvHD) is associated with a higher risk of relapse of the underlying malignant disease, severe aGvHD usually induces the occurrence of life-threatening complications such as severe infections. This article summarizes the current state of aGvHD prophylaxis and treatment.