Hypercalcemia in Cats: A Retrospective Study of 71 Cases (1991–1997)

Abstract

A retrospective study was conducted to characterize the diseases, clinical findings, and clinicopathologic and ultrasonographic findings associated with hypercalcemia (serum calcium concentration >11 mg/dL) in 71 cats presented to North Carolina State University Veterinary Teaching Hospital. The 3 most common diagnoses were neoplasia (n = 21), renal failure (n = 18), and urolithiasis (n = 11). Primary hyperparathyroidism was diagnosed in 4 cats. Lymphoma and squamous cell carcinoma were the most frequently diagnosed tumors. Calcium oxalate uroliths were diagnosed in 8 of 11 cats with urolithiasis. Cats with neoplasia had a higher serum calcium concentration (13.5 +/- 2.5 mg/dL) than cats with renal failure or urolithiasis and renal failure (11.5 +/- 0.4 mg/dL; P < .03). Serum phosphorus concentration was higher in cats with renal failure than in cats with neoplasia (P < .004). Despite the fact that the majority of cats with uroliths were azotemic, their serum urea nitrogen and creatinine concentrations and urine specific gravity differed from that of cats with renal failure. Additional studies are warranted to determine the underlying disease mechanism in the cats we identified with hypercalcemia and urolithiasis. We also identified a small number of cats with diseases that are not commonly reported with hypercalcemia. Further studies are needed to determine whether an association exists between these diseases and hypercalcemia, as well as to characterize the underlying pathophysiologic mechanism for each disease process.

Non-metastatic squamous cell carcinoma in two Hermann’s tortoises (Testudo hermanni)

“…In previous reports, hypercalcemia has not been described in reptiles with SCC but can be observed in humans cats and dogs with HHM. [19][20][21] The basis of the HHM in some of these patients could be associated with PTHrP synthesis by tumor cells, 22,23 whereas in others PTHrP synthesis was not identified. 24 In summary, SCC is a rare tumor in tortoises, although it is described in a few cases.…”

Hypercalcemia and Primary Hyperparathyroidism

“…The 1 to 13 region of PTHrP is 70% homologous with the corresponding region of parathyroid hormone (PTH) and is believed to be involved in activation of adenylate cyclase and other second-messenger systems in target tissues. About one-third of cats with lymphoma are hypercalcemic (Savary et al, 2000). The 35 to 108 region of PTHrP is unique, sharing no homology with any other known peptide.…”

“…Vomiting, diarrhea, and/or constipation were observed in 27%, polyuria and/or polydipsia were observed in 24%, urinary signs were seen in 23%, and neurologic signs were observed in 14% (Savary et al, 2000). In a study of 71 hypercalcemic cats, their mean age was about 9 years and their mean serum TCa concentration was 12.2 mg/dL.…”

“…Vomiting, diarrhea, and/or constipation were observed in 27%, polyuria and/or polydipsia were observed in 24%, urinary signs were seen in 23%, and neurologic signs were observed in 14% (Savary et al, 2000). Thus the differential diagnosis for hypercalcemia in cats is not dramatically different from that in dogs (Mealey et al, 1999;Savary et al, 2000;Pineda et al, 2012). The most common cancers diagnosed included lymphoma and squamous cell carcinoma.…”

<i>Notch2</i> Transduction by Feline Leukemia Virus in a Naturally Infected Cat

“…Hypercalcemia is commonly linked to malignancy in dogs and humans, especially in lymphoma [7, 23]. In most cases of feline lymphoma, elevation of the serum calcium concentration or parathyroid hormone-related peptide (PTHrP) is uncommon [2, 25]. Recently, an association between bone metabolism and Notch signaling has been revealed; RANKL-induced association of Notch2 and Jagged1 in pre-osteoclasts can lead to the differentiation into osteoclasts and activates osteoclastgenesis in them through the NF-κB pathway [9, 29].…”