ABSTRACT
Serum alkaline phosphatase (ALP) and its isoenzymes reflect bone metabolism: ALP increases the ratio of inorganic phosphate to pyrophosphate systemically and facilitates mineralization as well as reduces extracellular pyrophosphate concentration, an inhibitor of mineral formation. On the contrary, low ALP activity is associated with reduction of bone turnover. ALP includes four isoenzymes depending on the site of tissue expression: intestinal ALP, placental ALP, germ cell ALP and tissue nonspecific ALP or liver/bone/kidney ALP. The bone isoenzyme (B-ALP) is involved in bone calcification and is a marker of bone turnover as a result of osteoblastic activity. ALP and its isoenzymes are crucial in the diagnostic process of all the forms of rickets.The most common cause of rickets is vitamin D nutritional deficiency. The aim of this review is to update on the role played by ALP serum concentrations as a relevant marker in thediagnosis and treatment of rickets. Indeed, the diagnosis of rickets is based on its clinical, radiological and laboratory characteristics. An elevated ALP level is one of the markers for the diagnosis of rickets in children, though it is also associated with bone formation process. ALP is also useful for the differentiation between rickets and other disorders that can mimic rickets because of their clinical and laboratory characteristics, and, together with other biochemical markers, is crucial for the differential diagnosis of the different forms of rickets. Age, severity and duration of rickets may also modulate ALP elevation. Finally, ALP measurements are useful in clinical and therapeutic follow-up.
Subject(s)
Rickets , Vitamin D Deficiency , Pregnancy , Child , Humans , Female , Alkaline Phosphatase , Isoenzymes , Diphosphates , PlacentaABSTRACT
BACKGROUND: Filgrastim biosimilars have recently been introduced into clinical practice. To date biosimilars have demonstrated comparable efficacy and safety as the originator in chemotherapy-induced neutropenia. Published experience in engraftment after autologous stem cell transplantation (ASCT) is limited and concerns relatively few patients. MATERIALS AND METHODS: With the aim of assessing the efficacy and the safety of filgrastim biosimilars in post-ASCT bone marrow recovery, we conducted a single institution, retrospective study in 56 lymphoma and myeloma patients who received filgrastim biosimilars (Tevagrastim(®) and Zarzio(®)) at standard doses from day 5. We compared our results with recently published data on the originator. A cost analysis of each biosimilar was performed. RESULTS: Neutrophil counts recovered in 55 patients. The median number of filgrastim biosimilar vials injected was seven per patient. The median time to neutrophil and platelet recovery was 10 and 12 days, respectively. Twenty-six patients had febrile neutropenia, in half of whom the agent involved was identified. In the cost analysis, the use of Tevagrastim(®) and Zarzio(®) was associated with cost reductions of 56% and of 86%, respectively. DISCUSSION: Despite differences in CD34+ cell counts and time of starting filgrastim, our results in terms of time to engraftment and median number of vials injected are similar to published data. Comparing our results by single conditioning regimen to recent literature data, the time to engraftment and duration of hospitalisation were equivalent. Significant differences were observed in the incidence of febrile neutropenia, perhaps due to different preventive and prophylactic protocols for infections. Although prospective studies should be performed to confirm our results, filgrastim biosimilars were found to be effective and safe in engraftment after ASCT.