E-Poster Presentation 30th Australian and New Zealand Bone and Mineral Society Annual Scientific Meeting 2020

Severe urticarial rash secondary to internet-bought strontium citrate for osteoporosis management (#127)

Hannah Youn 1 , Rinky Giri 1 , Frances Milat 1 2 3
  1. Department of Endocrinology, Monash Health, Clayton, Victoria, Australia
  2. Hudson Institute of Medical Research, Clayton, Victoria, Australia
  3. Department of Medicine, School of Clinical Sciences, Clayton, Victoria, Australia

Strontium ranelate (SR) rose to popularity in the early 2000s with its promising benefits in osteoporosis management and fracture reduction. However, subsequent studies demonstrating increased risk of thrombo-embolism, cardiovascular disease and stroke have led to discontinuation of SR worldwide.(1-3) Cases of drug rash with eosinophilia and systemic symptoms (DRESS) were additionally reported with SR use. Patients with DRESS present with worsening rash, facial oedema, lymphadenopathy, elevated eosinophils and inflammatory markers which commence three to four weeks after SR initiation and require several weeks of tapering high-dose steroids to resolve.(4,5)

An alternative formulation of strontium, strontium citrate (Algaecal Strontium Boost), is currently sold over the internet as a supplement for managing low bone mineral density. Few studies have examined the safety of strontium citrate (SC); a 7-year longitudinal study funded by Algaecal reported nil adverse effects.(6) We present a case of a 30-year-old woman who obtained Algaecal Strontium Boost online for treatment of her osteoporosis, on a background of cerebral palsy, epilepsy, chronic kidney disease (secondary to reflux nephropathy) and subclinical hypothyroidism. She presented to the emergency department with worsening urticarial, maculopapular rash and mild lip swelling after two weeks of daily intake. She was afebrile, had normal inflammatory markers and normal eosinophil count. A skin biopsy demonstrated changes consistent with a drug reaction. She was commenced on oral prednisolone 100mg daily which was weaned and discontinued over one to two weeks. SC was also discontinued and the patient was prescribed topical Diprosone and Hydrocortisone therapy. Outpatient review one month afterwards reassuringly found almost complete resolution of her symptoms.
Patients should be aware of the potential risk of skin eruptions with strontium citrate and should discontinue and urgently seek medical advice if it occurs. Patients with osteoporosis are encouraged to discuss management options with their treating clinician.

 

References:

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  2. O’Donnell S, Cranney A, Wells GA, Adachi JD, Reginster JY. Strontium ranelate for preventing and treating postmenopausal osteoporosis. Cochrane Database Syst Rev [Internet]. 2006 Jul 19 [cited 2020 Aug 8];(3):CD005326, Available from: https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD005326.pub2/full doi: https://doi.org/10.1002/14651858.CD005326.pub2
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  4. Audran M, Jakob FJ, Palacios S, Brandi ML, Bröll H, Hamdy NA et al. A large prospective European cohort study of patients treated with strontium ranelate and followed up over 3 years. Rheumatol Int [Internet]. 2013 Mar 2 [cited 2020 Aug 9];33(9):2231-9. Available at: https://link.springer.com/article/10.1007%2Fs00296-012-2594-y doi: 10.1007/s00296-012-2594-y
  5. Cacoub P, Descamps V, Meyer O, Speirs C, Belissa-Mathiot P, Musette P. Drug rash with eosinophilia and systemic symptoms (DRESS) in patients receiving strontium ranelate. Osteoporos Int [Internet]. 2013 Jan 30 [cited 2020 Aug 9];24(5):1751-7. Available at: https://pubmed.ncbi.nlm.nih.gov/23361875/ doi: 10.1007/s00198-013-2265-1
  6. Kaats GR, Preuss HG, Stohs S, Perricone N. A 7-Year Longitudinal Trial of the Safety and Efficacy of a Vitamin/Mineral Enhanced Plant-Sourced Calcium Supplement. J Am Coll Nutr [Internet]. 2016 Feb 17 [cited 2020 Aug 9];35(2):91-99. Available at: https://pubmed.ncbi.nlm.nih.gov/26885697/ doi: 10.1080/07315724.2015.1090357