Hyperparathyroidism accompanying multiple myeloma

Hypophosphatemia in Patients With Multiple Myeloma

Hypophosphatemia is among the most common electrolyte abnormalities, especially among patients with underlying malignancies, and is frequently associated with adverse prognoses. Phosphorus levels are regulated through a number of mechanisms, including parathyroid hormone (PTH), fibroblast growth factor-23 (FGF-23), vitamin D, and other electrolyte levels themselves. Clinically, the findings are nonspecific, and the diagnosis is frequently delayed. This article is a narrative literature review. The PubMed database was searched for relevant articles pertaining to hypophosphatemia causes and consequences in patients suffering from multiple myeloma. We found a variety of causes of hypophosphatemia in patients with multiple myeloma. Tumor-induced osteopenia, although more common among patients with small squamous cell carcinomas, can occur with multiple myeloma as well. Additionally, both light chains themselves and medications can trigger Fanconi syndrome, which leads to phosphorus wasting by the kidney. Bisphosphonates, in addition to being a possible cause of Fanconi syndrome, lead to a decrease in calcium levels, which then stimulates parathyroid hormone (PTH) release, predisposing the patient to significant hypophosphatemia. Additionally, many of the more modern medications used to manage multiple myeloma have been associated with hypophosphatemia. A better understanding of those mechanisms may give clinicians a clearer idea of which patients may need more frequent screening as well as what the potential triggers in the individual patient may be.

A case of hypercalcemia with double pathology

Hypercalcemia has many causes including primary hyperparathyroidism, malignancy, and other rare etiologies. In most of the cases, hypercalcemia is secondary to one etiology. In this case, we are reporting hypercalcemia with two causes. The initial workup showed primary hyperparathyroidism due to parathyroid adenoma. But because all features were not fully explained by primary hyperparathyroidism, further work-up revealed multiple myeloma. This case represents coexistence of two different diseases, which was rarely reported in the literature previously. Usually, the co-diagnosis was made subsequently after failure to correct hypercalcemia. In our case, both diagnoses were established at the same time of the patient’s presentation as of high suspicion. Establishing the diagnosis early will aid in the initiation of treatment in a timely fashion.

A case of multiple myeloma coexisting with primary hyperparathyroidism and review of the literature

Hypercalcemia is a common medical problem with an estimated prevalence of 15% among hospitalized patients. Multiple myeloma (MM) and primary hyperparathyroidism (PHPT) are among the most common causes of hypercalcemia but coexistence of both pathologic processes in a patient is an extremely rare phenomenon. In this paper we have discussed a patient presenting with this rare phenomenon. We have also provided a comprehensive review of the scientific literature published on codiagnosis of MM and PHPT.

Malignant myeloma in a patient after treatment for osteoporosis with teriparatide; a rare coincidence

A breakthrough in understanding of mechanisms of bone structure regulation has brought about the introduction of the new synthetic recombinant human parathyroid hormone 1–34 (PTH1-34; Teriparatide) in the treatment of osteoporosis. These mechanisms, involving the RANKL, RANK, and osteoprotegerin system, are also known to be involved in malignant myeloma (MM) and tumor and bone metastasis development.

We report a case in which MM was found after treatment of osteoporosis with teriparatide. We were unable to demonstrate any direct association between the MM and teriparatide treatment. However, it seemed intriguing that similar mechanisms are activated in the development of MM as those being working during teriparatide treatment.

In the view of our case, we propose that MM by examination of serum protein fraction should be searched for prior to treatment with teriparatide as it is an exclusion criterion in teriparatide treatment of secondary osteoporosis. A search for other metastatic diseases prior to teriparatide treatment should eventually also be considered. The theoretical basis for our proposal is discussed.

[Hypercalcemia of double origin: association of multiple myeloma and ectopic parathyroidal adenoma]

INTRODUCTION

Multiple myeloma and primary hyperparathyroidism are two causes of hypercalcemia. This association has already been described to be not casual, despite their link is still unknown.

OBSERVATION

We describe a 68 years old woman, without notable background, was admitted for low back pain. Biology showed an IgG Kappa multiple myeloma (stade 3) and an hypercalcemia without renal failure. Hypercalcemia was difficult to control with bisphosphonate and calcitonin. At first, there was also an hypophosphoremia and a high parathormone level (287 pg/ml). Imaging showed spread myeloma impairment and a right paramediastinal tissular mass. Biopsy diagnosed an ectopic parathyroidal adenoma.

DISCUSSION

Multiple myeloma and primary hyperparathyroidism can be associated. They are often revealed by an hypercalcemia difficult to control or refractory to the treatment. Hypophosphoremia can suggest the diagnosis of hyperparathyroidism. Both this observation and litterature (about twenty case reports) suggest that this double diagnosis should be systematicly evoked and explored by an assay of parathormone and a seric proteins electrophoresis in all hypercalcemia.

CONCLUSION

Multiple myeloma and parathyroidal adenoma should be both explored in all hypercalcemia, because they can be associated.