Metformin İlişkili Laktik Asidoz: Bir Vaka Sunumu

Abstract

Metformin, tip 2 diyabetes mellitus (DM) tedavisinde yaygın olarak kullanılan etkili ve güvenli bir oral antidiyabetiktir. Ancak nadir görülen fakat mortalitesi yüksek bir komplikasyonu olan metformin ilişkili laktik asidoz (MALA), özellikle predispozan risk faktörlerinin varlığında hayatı tehdit edici bir tabloya yol açabilir. Bu çalışmada, endoskopik işlem hazırlığı sırasında gelişen hipovolemi sonrası akut böbrek hasarı ve ağır laktik asidoz gelişen bir MALA olgusu sunulmaktadır. Tip 2 DM nedeniyle metformin kullanan 56 yaşındaki erkek hasta, endoskopi hazırlığı sonrası gelişen bulantı, kusma ve idrar çıkışında azalma ile başvurdu. Laboratuvar testlerinde ağır metabolic asidoz (pH: 7,05; HCO₃⁻: 8,9 mmol/L; laktat: 21 mmol/L) ve ciddi böbrek fonksiyon bozukluğu (kreatinin: 11,91 mg/dL) saptandı. Klinik ve biyokimyasal bulgularla MALA tanısı konulan hastaya acil hemodiyaliz ve yoğun intravenöz hidrasyon uygulandı. Tedavi sonrası hastanın metabolic parametreleri hızla düzeldi ve diyaliz gereksinimi ortadan kalktı. Poliklinik kontrollerinde renal fonksiyonlarının tamamen normale döndüğü gözlendi. MALA, özellikle renal fonksiyonları etkileyebilecek durumlarda metformin kullanımının devam ettiği olgularda ciddi sonuçlara yolaçabilir. Bu vaka, invaziv işlem hazırlığında metforminin kesilmemesinin potansiyel risklerini ortaya koymakta ve işlem öncesi dönemde metformin tedavisinin durdurulmasının önemine dikkat çekmektedir. MALA şüphesi bulunan olgularda erken tanı ve tedavi, mortaliteyi azaltmada kritik rol oynamaktadır.

Keywords

• Metformin
• laktik asidoz
• MALA
• akut böbrek hasarı
• hemodiyaliz
• endoskopi hazırlığı

Metformin-Associated Lactic Acidosis: A Case Report

Abstract

Metformin is a widely prescribed and effective oral antidiabetic agent used in the treatment of type 2 diabetes mellitus (DM). Although generally well tolerated, metformin-associated lactic acidosis (MALA) is a rare but potentially fatal complication, especially in the presence of predisposing risk factors. Herein, we present a case of MALA that developed after volume depletion related to bowel preparation for endoscopic procedures. A 56-year-old male patient with type 2 diabetes mellitus who was taking metformin presented with nausea, vomiting, and decreased urine output following endoscopy preparation. Laboratory tests revealed severe metabolic acidosis (pH: 7.05; HCO₃⁻: 8.9 mmol/L; lactate: 21 mmol/L) and severe renal dysfunction (creatinine: 11.91 mg/dL). The patient was diagnosed with MALA based on clinical and biochemical findings and underwent emergency hemodialysis and intensive intravenous hydration. After treatment, the patient's metabolic parameters improved rapidly and the need for dialysis disappeared. Outpatient follow-up revealed that renal function had returned to normal. This case underscores the potential risk of continuing metformin therapy during peri-procedural periods associated with volume depletion. The omission of pre-procedural discontinuation of metformin in our patient likely contributed to the development of life-threatening lactic acidosis. Early diagnosis and timely initiation of renal replacement therapy are critical for reducing mortality in MALA cases.

Keywords

• Metformin
• lactic acidosis
• MALA
• acute kidney injury
• hemodialysis
• endoscopic preparation

References

1. DeFronzo R, Fleming GA, Chen K, Bicsak TA. Metformin-associated lactic acidosis: Current perspectives on causes and risk. Metabolism: clinical and experimental. 2016; 65(2), 20–29.
2. Kuan IHS, Savage RL, Duffull SB, Walker RJ, Wright DFB. The Association between Metformin Therapy and Lactic Acidosis. Drug safety. 2019; 42(12), 1449–1469.
3. Lalau JD, Race JM. Lactic acidosis in metformin therapy: searching for a link with metformin in reports of “metformin-associated lactic acidosis”. Diabetes Obes Metab. 2001; 3(3): 195–201.
4. Lipska KJ, Bailey CJ, Inzucchi SE. Use of metformin in the setting of mild-to-moderate renal insufficiency. Diabetes Care. 2011; 34(6): 1431–7.
5. Yang, C. C., Weng, S. F., Tseng, K. L., & Ho, C. H. (2022). Clinical presentations and prognosis of metformin-associated lactic acidosis patients in the intensive care unit: A 20-year survey. Medicine, 101(27), e29918.
6. Kajbaf F, Lalau JD. The prognostic value of blood lactate concentrations in acute metformin overdose with lactic acidosis. Crit Care. 2013; 17(5): R210.
7. Luft D, Deichsel G, Schmülling RM, Stein W, Eggstein M. Metformin-induced lactic acidosis: incidence and prognostic relevance. Diabetologia. 1978; 14(2): 75–87.
8. NICE Guideline. Type 2 diabetes in adults: management. NG28. National Institute for Health and Care Excellence; 2015.

9. British National Formulary. Metformin: cautions and monitoring. Available from: https://bnf.nice.org.uk
10. American Diabetes Association. Standards of Medical Care in Diabetes—2023. Diabetes Care. 2023;46(Suppl 1):S1–291.
11. Royal Australian College of General Practitioners. Metformin and contrast imaging procedures. Available from: https://www.racgp.org.au
12. Seidowsky A, Nseir S, Houdret N, Fourrier F. Metformin-associated lactic acidosis: a prognostic and therapeutic study. Crit Care Med. 2009; 37(7): 2191–6.
13. Mariano F, Pozzato M, Inguaggiato P, Guarena C, Turello E, Manes M et al. Metformin-Associated Lactic Acidosis Undergoing Renal Replacement Therapy in Intensive Care Units: A Five-Million Population-Based Study in the North-West of Italy. Blood Purif. 2017; 44(3): 198-205.
14. Protti A, Russo R, Tagliabue P, Vecchio S, Singer M, Bellani G. Oxygen consumption is not impaired in critically ill patients with metformin-associated lactic acidosis. Intensive Care Med. 2012; 38(1): 92–9.
15. See K. C. (2024). Metformin-associated lactic acidosis: A mini review of pathophysiology, diagnosis and management in critically ill patients. World journal of diabetes, 15(6), 1178–1186.