Severe hypophosphataemia in autograft recipients during accelerated leucocyte recovery

Serum electrolyte dynamics in multiple myeloma patients undergoing autologous haematopoietic stem cell transplantation

AIM

High-dose melphalan followed by autologous haematopoietic cell transplantation remains the standard-of-care therapy for multiple myeloma (MM). Gastrointestinal toxicity concomitant with electrolyte derangement is a primary cause of morbidity from transplant. Here, we assessed the dynamics of electrolyte imbalances and its role in hematologic counts and engraftment. Ω Patients and Methods One hundred and eighteen MM patients that received transplant were studied.

RESULTS

Engraftment speed (ES) was calculated as the period between the first rise in the absolute neutrophil count (ANC) and full engraftment defined as the first of three consecutive days with ANC > 500 × 10⁶ /L. The defined median ES was 2 days (range 0-5 days) and 40 patients had ES ≤2 days. Engraftment occurred at a median of 10 days. The median time-to-nadir for phosphorus and potassium was 10 and 4.28 days, respectively. The drop in phosphorus and potassium serum level was statistically greater in patients with an ES ≤2 days compared to patients with ES ≥2 days. Magnesium level were not significantly affected and there was no significant difference between the drop in serum phosphorus and potassium based on severity of nausea or oral mucositis.

CONCLUSION

Our results indicate that there is a significant correlation between the magnitude of drop in potassium and phosphorous levels and a steep rise in neutrophil counts around the engraftment period following stem cell transplant. These events indicate a "genesis syndrome" characterized by a rapid, massive transfer of electrolytes into proliferating cells as has been previously described after HCT for certain high-grade lymphomas and leukemias.

Total parenteral nutrition in children and adolescents treated with high-dose chemotherapy followed by autologous haematopoietic transplants

Total parenteral nutrition (TPN) is still of great importance for haematopoietic stem cell transplantation (HSCT) patients because one of the major adverse effects of the high-dose therapy followed by HSCT is an inadequate oral nutrition intake. The aim of the study was analysis of TPN of young patients in the HSCT period. Twenty-two patients 1·8–20·8 year-old, median 5·4, treated with high-dose therapy and autologous HSCT because of malignancy were included into the study. Grafts contained 1·35–7·9 × 106, median 3·75 × 106CD34+ cells/kg. Engraftment occurred as follows: granulocytes >0·5 × 109/l on +11 d (8–25); platelets >20 × 109/l on +23 d (12–67). Patients were given isoenergetic, isonitrogenous TPN until they consumed less than 50 % of their required diet orally. Proteins intake was 0·8–2·0 g/kg per d, fats intake 1·0–3·0 g/kg per d. Total non-proteins energies–nitrogen grams index was 140:1–200:1. Supplementation of electrolytes, microelements, trace elements and vitamins was dependent on individual patient requirement. TPN duration did not correlate with CD34+cells number but correlated with platelets reconstitution. The assessment of nutritional condition demonstrated no differences in anthropometric parameters, but increase of serum albumin levels after TPN. Requirement for P3 − was above the normal ranges and correlated positively with platelets reconstitution. Requirement for P3 − and K+was higher in patients with mucositis than in other patients. Any complications due to TPN were observed. Adequately composed isoenergetic and isonitrogenous TPN with replacement of electrolytes according to their requirement in the early post-transplantation period allows not only improvement in nutritional status of patients but also could contribute to reconstitution of haematopoiesis.

Post-renal transplantation hypophosphatemia: a review and novel insights

PURPOSE OF REVIEW

This review intends to elucidate the pathophysiologic mechanism of renal phosphorus loss in the post-renal transplantation population. This review will provide new insight in to the pathophysiologic mechanism(s) responsible for the development of this phenomenon and will also explore the pathogenetic role of persistent phosphorus wasting in the development of post-renal transplantation osteodystrophy.

RECENT FINDINGS

Recently, the phosphaturic hormone, fibroblast growth factor-23, has been ascertain to be increased in the sera of patients with chronic kidney and end-stage renal disease. There is new evidence that a non-PTH humoral factor is persistently present in post-renal transplantation patients that is likely responsible for the observed persistent renal phosphorus loss. We offer that fibroblast growth factor-23 (and/or other phosphatonins) is the culprit factor responsible for the phenomenon of persistent hypophosphatemia in post-renal transplantation patients. Moreover, we believe that the phenomenon of persistent renal phosphorus wasting is an important but overlooked cause of osteodystrophy and increased fracture risk in this patient population.

SUMMARY

The pathophysiology of post-renal transplantation phosphorus wasting is complex and to date is still not fully recognized. Further studies of the regulatory mechanism of fibroblast growth factor-23 and its metabolism may offer additional insights into phosphorus homeostasis and its clinical application in the post-renal transplantation population.

Hypophosphatemia and hypouricemia in pediatric allogeneic bone marrow transplant recipients

Increased phosphate (P) uptake by the replicating neutrophils during engraftment syndrome has been described to play a role in the development of hypophosphatemia (HP) in bone marrow transplantation patients, and suggested as a measure of neutrophil recovery. Here, the relationship of serum P with engraftment was determined in 56 children who underwent allogeneic bone marrow transplantation (BMT). Uric acid (UA) levels were also analyzed to study the contribution of cytolysis on P levels. HP and hypouricemia (HU) developed at least once in 63 and 57% of patients respectively, before and until day +20 after transplantation. The minimal values of P and UA were observed at day +10 and were significantly lower than the baseline values (p < 0.01). The mean neutrophil engraftment was at day +13, following the P and UA nadir by 3 days. In addition there was a significant correlation between P and UA levels (p = 0.01). The levels of of both P and UA returned to pretransplant values at day +20. A significant correlation (p < 0.05) between platelet engraftment and P levels was also demonstrated. HP and HU seen in pediatric patients undergoing BMT reflects a combination of pathophysiologic mechanisms.

Engraftment-associated hypophosphatemia--the role of cytokine release and steep leukocyte rise post stem cell transplantation

Hypophosphatemia associated with bone marrow transplantation has been infrequently reported. The suggested mechanism is phosphate uptake by the replicating cells. Various cytokines are associated with the development of hypophosphatemia. The present study evaluated the interrelationship between cytokine release, the rise in WBC and the development of hypophosphatemia during the engraftment period. Blood samples were obtained from 60 patients undergoing peripheral blood stem cell transplant, on the day of admission and then daily from the day of transplant until discharge. Hypophosphatemia developed in 62% of the patients. The median day of minimal phosphorus level was +8 and it antedated engraftment by 2 days. There was a significant correlation between the day of minimal phosphorus level and the day of maximal WBC and a significant correlation between the fall in phosphorus level and WBC rise. IL-6 and IL-8 showed similar kinetics. Higher IL-6 and IL-8 levels were directly associated with lower phosphorus levels. In conclusion, hypophosphatemia commonly occurs in the post-transplant period. We assume that both a direct effect of cytokine release and an increased consumption by the dividing WBCs contribute to its appearance. As its occurrence usually antedates engraftment it can be used as a forerunner for WBC recovery.

Severe hypophosphatemia during hematopoietic reconstitution after allogeneic peripheral blood stem cell transplantation

A patient suffering from acute myeloid leukemia (FAB M5a) received a PBSC allograft from a matched, related donor. On day 13 after transplantation severe hypophosphatemia (0.21 mmol/l) was first noted which persisted irrespective of intravenous phosphate administration, and within 2 days reached concentrations below 0.13 mmol/l. After repeated phosphate substitution serum phosphate returned to 1.40 mmol/l on day 17. Phosphate in urine, and calcium in serum were recorded as unchanged throughout. Clinical signs and symptoms due to severe hypophosphatemia were not observed except for paresthesia in the lower extremities. The precipitous fall in serum phosphate coincided with hematopoietic reconstitution as reflected by a steep rise in leukocyte count from 0.08 x 109/l on day 10 to 5. 94 x 109/l on day 15 after transplantation. Thus, isolated hypophosphatemia was likely the result of excessive cellular phosphate uptake during hematopoietic reconstitution. Electrolyte monitoring after PBSCT should include serum phosphate to identify the hypophosphatemia associated with hematopoietic recovery.