Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2024 Jul 11;391(2):167-176.
doi: 10.1056/NEJMcpc2402485.

Case 21-2024: A 10-Month-Old Boy with Vomiting and Hypercalcemia

Christina Jacobsen  1 , Harald Jüppner  1 , Deborah M Mitchell  1
Affiliations
Case Reports

Case 21-2024: A 10-Month-Old Boy with Vomiting and Hypercalcemia

Christina Jacobsen et al. N Engl J Med. .
No abstract available

PubMed Disclaimer

Figures

Figure 1.
Figure 1.. Growth Curves.
The growth curves show the patient’s body weight (Panel A) and length (Panel B) relative to the average values for boys in his age group. The solid lines indicate growth percentile, and the gray dots indicate growth points before and at the time of this evaluation. The patient had shown normal growth until 9 months of age, when the rate of weight gain and length increase leveled abruptly. At 6 months of age, the weight was 7.39 kg (27.1st percentile) and the length 66.7 cm (43.1st percentile); at 9 months of age, the weight was 7.44 kg (1.6th percentile) and the length 68.2 cm (6.5th percentile).
Figure 2.
Figure 2.. Differential Diagnosis for PTH-Independent Hypercalcemia.
Shown is a schematic diagram of the differential diagnosis for parathyroid hormone (PTH)–independent hypercalcemia, which has been simplified to include only diagnoses that would be appropriate for pediatric patients in the first year of life. After the patient is found to have hypercalcemia and a low PTH level, decision making is guided by the evaluation of the 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels. If the 25-hydroxyvitamin D level is high, vitamin D intoxication is included in the differential diagnosis. PTHrP denotes PTH-related peptide.
Figure 3.
Figure 3.. Metabolism of Vitamin D.
Vitamin D is converted to 25-hydroxyvitamin D (25[OH]D) by a 25-hydroxylase and then to the active form 1,25-dihydroxyvitamin D (1,25[OH]2D) by a 1α-hydroxylase encoded by CYP27B1. Both 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D can be inactivated either by the 24-hydroxylase enzyme encoded by CYP24A1 or by oxidation by CYP3A4. Nonpharmacologic therapies for 24-hydroxylase deficiency include restricting dietary intake of calcium and vitamin D, as well as avoiding endogenous production of vitamin D through limiting exposure to ultraviolet B (UVB) light. Azole antifungal medications, such as ketoconazole and fluconazole, can reduce the level of circulating 1,25-dihydroxyvitamin D by inhibiting CYP27B1. Rifampin, certain antiepileptic medications, and other inducers of CYP3A4 can accelerate the breakdown of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D through stimulation of this alternative catabolic pathway. 1,24,25(OH)3D denotes 1,24,25-trihydroxyvitamin D.
Figure 4.
Figure 4.. CYP24A1.
CYP24A1, the gene encoding the 24-hydroxylase enzyme, is located on the long arm of chromosome 20. It comprises 12 exons that are transcribed in the opposite direction (i.e., telomeric to centromeric). Thus, leucine (Leu, L) at position 409 is encoded by TTA on the complementary strand and the T-to-C change at nucleotide position c.1226 (rs6068812) that was identified in the patient generates codon TCA, which encodes serine (Ser, S).
See this image and copyright information in PMC

References

    1. Walker MD, Shane E. Hypercalcemia: a review. JAMA 2022;328:1624–36. - PubMed
    1. Tebben PJ, Singh RJ, Kumar R. Vitamin D-mediated hypercalcemia: mechanisms, diagnosis, and treatment. Endocr Rev 2016;37:521–47. - PMC - PubMed
    1. Stokes VJ, Nielsen MF, Hannan FM, Thakker RV. Hypercalcemic disorders in children. J Bone Miner Res 2017;32:2157–70. - PMC - PubMed
    1. Motlaghzadeh Y, Bilezikian JP, Sellmeyer DE. Rare causes of hypercalcemia: 2021 update. J Clin Endocrinol Metab 2021;106:3113–28. - PubMed
    1. Goltzman D Nonparathyroid hypercalcemia. Front Horm Res 2019;51:77–90. - PubMed

Publication types