Successful Conservative Management of Trimethoprim Induced Life-Threatening Hyperkalaemia in a Patient with Pneumocystis jirovecii Pneumonia


Co-trimoxazole is a combination antibiotic made up of trimethoprim and sulphamethoxazole that is first line treatment for Pneumocystis jirovecii pneumonia (PJP). Hyperkalaemia is a relatively common side effect of the trimethoprim component of co-trimoxazole but it is not well recognised by clinicians. The mechanism of action causing hyperkalaemia due to trimethoprim is similar to the potassium sparing diuretic effect of amiloride. It has been suggested on this basis that the hyperkalaemia can be reversed by the administration of furosemide and 0.9% saline to promote kaliuresis. We present what we believe to be the first published case of successfully managing trimethoprim induced hyperkalaemia with furosemide and 0.9% saline allowing the continued use of co-trimoxazole to treat severe PJP.

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Johnstone, J. and Macduff, A. (2014) Successful Conservative Management of Trimethoprim Induced Life-Threatening Hyperkalaemia in a Patient with Pneumocystis jirovecii Pneumonia. Case Reports in Clinical Medicine, 3, 469-473. doi: 10.4236/crcm.2014.38103.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Sax, P.E. (2012) Treatment of Pneumocystis Infection in HIV-Infected Patients. Uptodate Article.
[2] Kaufman, A.M., Hellman, G. and Abramson, R.G. (1983) Renal Salt Wasting and Metabolic Acidosis with Trimethoprim-Sulfamethoxazole Therapy. The Mount Sinai Journal of Medicine, 50, 238-239.
[3] Perazella, M.A. (2000) Trimethoprim-Induced Hyperkalaemia: Clinical Data, Mechanism, Prevention and Management. Drug Safety, 22, 227-236.
[4] Safrin, S. and Finkelstein, D.M. (1997) Comparison of Oral Agents for the Treatment of Pneumocystis carinii Pneumonia [Letter]. Annals of Internal Medicine, 126, 407-408
[5] Alappan, R., Buller, G.K. and Perazella, M.A. (1999) Trimethoprim-Sulfamethoxazole Therapy in Outpatients: Is Hyperkalemia a Significant Problem? American Journal of Nephrology, 19, 389-394.
[6] Velazquez, H., Perazella, M.A., Wright, F.S. and Ellison, D.H. (1993) Renal Mechanism of Trimethoprim-Induced Hyperkalemia. Annals of Internal Medicine, 119, 296-301.
[7] Stangoe, D., Jenkins, N. and Coakes, J. (2013) A Case or Refractory Hyperkalaemia in an HIV-Positive Patient with Pneumoncystis jirovecii Pneumonia. JCIS, 14, 259-262.
[8] Antoniou, T., Gomes, T., Mamdani, M.M., Yao, Z., Hellings, C., Garg, A.X., Weir, M.A. and Juurlink, D.N. (2011) Trimethoprim-Sulfamethoxazole Induced Hyperkalaemia in Elderly Patients Receiving Spironolactone: Nested Case-Control Study. BMJ, 343, Article ID: d5228.
[9] Greenberg, S., Reiser, I.W., Chou, S.Y. and Porush, J.G. (1993) Trimethoprim-Sulfamethoxazole Induces Reversible Hyperkalemia. Annals of Internal Medicine, 119, 291-295.
[10] Bennett, N.J. (2013) Pneumocystis jirovecii Pneumonia. Emedicine Article.

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