European Journal of Case Reports in Internal Medicine - © EFIM
Objective: To describe hypocalcaemia due to vitamin D deficiency in ‘hikikomori’ syndrome.
Materials and methods: A 37-year-old man with ‘hikikomori’ syndrome for a year was admitted with hypocalcaemia (serum ionic calcium 1.17 mmol/l). Serum 1,25(OH)2-vitamin D3 determined by liquid chromatography–tandem mass spectrometry was depressed at 12.1 pg/ml (29.0 pmol/l) and plasma intact PTH elevated at 324 ng/l. Administration of 1 μg/day 1α(OH)-vitamin D3 and 1 g/day calcium lactate for 1 week normalized calcium and PTH, and raised 1,25(OH)2-vitamin D3 to low normal levels.
Conclusion: This is the first report of hypocalcaemia due to vitamin D deficiency in a patient with ‘hikikomori’ syndrome.
Hikikomori syndrome, Hypocalcemia, Hypovitaminosis D
- Watts J. Public health experts concerned about 'hikikomori'. Lancet 2002;359:1131.
- Kato TA, Tateno M, Shinfuku N, et al. Does the 'hikikomori' syndrome of social withdrawal exist outside Japan? A preliminary international investigation. Soc Psychiatry Psychiatr Epidemiol 2012;47:1061–1075.
- Herrmann M, Farrell CL, Pusceddu I, Fabregat-Cabello N, Cavalier E. Assessment of vitamin D status - a changing landscape. Clin Chem Lab Med 2016;55:3–26.
- Mochizuki A, Kodera Y, Saito T, et al. Preanalytical evaluation of serum 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 measurements using LC-MS/MS. Clin Chim Acta 2013;420:114–120.
- Satoh M, Ishige T, Ogawa S, et al. Development and validation of the simultaneous measurement of four vitamin D metabolites in serum by LC-MS/MS for clinical laboratory applications. Anal Bioanal Chem 2016;408:7617–7627.