Transient hyperphosphatasemia in pediatric renal transplant patients – Is there a need for concern and when?

Abstract

TH of infancy and early childhood is characterized by transiently increased S-ALP, predominantly its bone or liver isoforms. There are neither signs of metabolic bone disease or hepatopathy corresponding to the increased S-ALP, nor a common underlying/triggering disease. TH may also occur in children post-renal Tx, which may raise significant concerns and anxiety. We describe four patients aged 2.8-7 yr in whom the TH occurred at 11-34 (median = 28) months after Tx and lasted from 40 to 105 (median = 63) days. No obvious cause/trigger of TH could be found; the clinical status and bone turnover were not altered. In cases of TH post-Tx, we recommend the evaluation of basic biochemical indices and wrist X-ray. If these results are normal, TH is most likely the diagnosis and the S-ALP can be monitored over the next three months without further testing. In patients with persisting TH for more than three months and/or in children with pre-existing or suspected metabolic bone disease, further evaluation may be indicated. In conclusion, TH is a benign disorder in patients post-Tx. Detailed investigation including bone biopsy is only indicated in patients with persisting TH.

Transient hyperphosphatasemia after pediatric liver transplantation

“…The prevalence of TH after LT in the present study was significantly higher than that in healthy children ( P < 0.05). Two possible reasons for this are as follows: (i) patients who undergo LT receive immunosuppressive agents, rendering them immunologically naive and vulnerable to infection by the aforementioned viruses; and (ii) TH is typically discovered during “routine blood testing” and is more likely to be detected in those patients undergoing frequent detailed investigation . Agarose gel electrophoresis was performed only in two studies, including the present study.…”

Benign transient hyperphosphatasemia in children

“…When it comes to children, the most common illnesses accompanied by BTH are various infections, usually viral, and rarely other pathological conditions [1-5, 10, 11, 14, 22, 23, 24]. Also, BTH occurs as part of the use of some drugs, such as sulfamethoxazole/ trimethoprim, cyclosporine, methotrexate and 6-mercaptopurine, as well as after renal and liver transplantation [25][26][27][28]. There are descriptions of rare cases of benign familial hyperphosphatasemia [29,30].…”

Transient hyperphosphatasemia in three pediatric patients treated with cyclosporine

“…Transient hyperphosphatasemia has occurred in association with a variety of clinical conditions, including respiratory infection, diarrheal disease, and urinary tract infection . TH has also been reported in association with kidney or liver transplantation, and in children receiving chemotherapy for leukemia and lymphoma . Approximately one‐third of TH cases were detected incidentally on occasional check‐up in healthy patients or in those with temporary illness.…”

“…1 Some drugs are suspected to contribute to the development of TH, but no clear evidence has been shown to date. 2 In this report, we present three cases involving pediatric patients with TH. All three patients were treated with cyclosporine.…”

“…Transient hyperphosphatasemia is a benign condition, and spontaneous recovery occurs within 4 months in 80% of affected patients . Some drugs are suspected to contribute to the development of TH, but no clear evidence has been shown to date …”