Acute Lymphoblastic Leukemia with Malignant Hypercalcemia: A Case Report

Successful Management of Severe Hypercalcemia with Zoledronic Acid: A Report of Two Pediatric Cases

Severe hypercalcemia associated with vitamin D intoxication or malignancy in children is a rare and life-threatening condition. There is little published experience with Zoledronic acid (ZA) in the treatment of pediatric severe hypercalcemia. Here, we present two pediatric cases of severe hypercalcemia, one due to vitamin D intoxication and the second to malignancy, in which ZA was used as the first-line bisphosphonate in the treatment. While both cases responded well to a single dose of ZA, the second case experienced hypocalcemia requiring calcium treatment after ZA infusion. Our report shows that ZA may be an effective option in the treatment of severe pediatric hypercalcemia, although patients should be followed closely after infusion due to the risk of hypocalcemia. We provide additional published evidence for the effectiveness of ZA in correcting severe pediatric hypercalcemia and hope this will encourage future studies with larger numbers of patients.

Malignant hypercalcemia as the debut of acute lymphoblastic leukemia in a pediatric patient-a diagnostic and therapeutic approach: Case report

Background

Hypercalcemia is a rare metabolic disorder in the pediatric population, with several differential diagnoses that resemble hematologic malignancies. In cases of severe hypercalcemia, therapeutic strategies other than hyperhydration, such as the use of bisphosphonates, have been described.

Case presentation

We present the case of a previously healthy 12-year-old boy who was admitted to the emergency department due to fatigue, hypo-responsiveness, and progressively worsening poor appetite for the previous 19 days. Initial laboratory tests revealed severe hypercalcemia (total calcium: 19 mg/dl), hyperphosphatemia, elevated creatinine, and hyperuricemia. Management with hyperhydration and xanthine oxidase inhibitor (allopurinol) was provided. The patient was transferred to the pediatric intensive care unit where treatment with furosemide, systemic corticosteroid, and zoledronic acid was started. Metabolic, infectious, renal, and endocrinological causes were excluded. Follow-up paraclinical studies showed a progressive hematologic involvement with heterogeneous hypochromic microcytic anemia, thrombocytopenia, and elevated lactic dehydrogenase. Bone marrow aspiration and biopsy were performed, which confirmed the diagnosis of B-precursor acute lymphoblastic leukemia. Hypercalcemia was resolved 72 h after the application of bisphosphonates.

Conclusion

Hypercalcemia as an oncological metabolic emergency in the onset of acute lymphoblastic leukemia is uncommon in children. The use of intravenous bisphosphonates is an effective therapy in the early resolution of the condition. We present the case of a 12-year-old patient with malignant hypercalcemia who responded favorably to the use of a single dose of bisphosphonates.

Ectopic parathyroid hormone as a rare aetiology of hypercalcemia with rhabdomyosarcoma: a new treatment strategy with zoledronic acid and Denosumab

OBJECTIVES

Ectopic parathyroid hormone (PTH) secretion is rare in children with rhabdomyosarcoma, and only a few pediatric cases have been reported to date. Reports of the use of zoledronic acid (ZA) and Denosumab are limited for the treatment of hypercalcemia of malignancy (HCM) in the pediatric population. The aim of presenting this pediatric case of rhabdomyosarcoma accompanied by HCM, secondary to ectopic PTH secretion, was to highlight the benefits of ZA as a first-choice bisphosphonate in this situation with Denosumab as an alternative therapy.

CASE PRESENTATION

The patient was diagnosed at 13 years with alveolar rhabdomyosarcoma. Multiple bone metastases first appeared at 15 years, but he remained normocalcemic until 17 years old when serum calcium was 15.1 mg/dL and PTH 249 pg/mL. While serum calcium responded well after ZA and Denosumab cycles, PTH remained elevated, reaching a peak value of 1851 pg/mL during treatment cycles.

CONCLUSIONS

We report a patient with rhabdomyosarcoma accompanied by HCM, secondary to ectopic PTH, in whom the HCM was successfully managed with ZA and Denosumab. We believe that ZA should be the bisphosphonate of choice in pediatric HCM with rhabdomyosarcoma, while Denosumab may be another option in ZA-refractory cases.

Hypercalcemia and Osteolytic Lesions as Presenting Symptoms of Acute Lymphoblastic Leukemia in Children: Case Report and Literature Review

Acute lymphoblastic leukemia (ALL) presenting with hypercalcemia and osteolytic lesions is rare and unusual in childhood. We report a case of a 13-year-old boy with ALL who presented with intermittent fever, nausea, vomiting, and increasing lower limb pain. Skeletal X-rays and CT scan showed severe osteolytic lesions of the skull and extremities. Physical examination revealed multiple inguinal lymph nodes. Laboratory tests demonstrated severe hypercalcemia (Ca > 3.49 mmol/L), decreased parathyroid hormone (PTH), and vitamin D level. Despite a normal complete blood count and the absence of circulating blasts, bone marrow biopsy revealed B-precursor ALL. Hypercalcemia was initially treated with intravenous isotonic sodium chloride and furosemide but the serum calcium level was not normalized. It was successfully managed with calcitonin and pamidronate afterward. Later, the child responded well to chemotherapy and continued with consolidation treatment. The clinical condition was stable, and the bone marrow revealed complete remission. This case indicated that hypercalcemia alone or combined with osteolytic lesions can be the only presenting symptom of ALL in children. Diagnostic errors may occur especially when combined with the absence of circulating blasts in the peripheral blood smear. Bone marrow aspiration should be considered to confirm the diagnosis.