Case sharing of the new hypoglycemic drug DPP-4i may cause adverse skin reactions. Which patients are at high risk?

Yimaitong compiles and organizes, please do not reprint without authorization
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Introduction: Recently, Dr.
Hiroki Maita of the Hongsaki University School of Medicine in Japan published a case in the Journal of General and Family Medicine, reporting a case of severe edema and blood blister related to sitagliptin
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It is recommended that clinicians take the dipeptidyl peptidase-4 inhibitor (DPP-4i) into consideration when diagnosing and treating patients with unexplained edema and blood blister
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The case sharing patient is a 79-year-old female with high blood pressure, diabetes, osteoporosis, and constipation.
She was referred to our hospital due to severe edema and blood blisters in her lower limbs (Figure 1A)
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The patient was diagnosed with diabetes 4 years ago.
He was treated with sitagliptin for 3 years, and his blood pressure and blood sugar levels were well controlled.
Before the symptoms appeared, he weighed 54kg
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About 3 years ago, the patient developed edema of both lower extremities, which progressed slowly, and was examined in detail in a primary care hospital
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Non-contrast CT showed a tumor in the left adrenal gland, and no hormone abnormalities were found in the endocrine examination, and he was diagnosed with a non-functional adrenal tumor
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No obvious abnormalities were found in other blood tests and venous ultrasound of the lower extremities
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A few months ago, the edema worsened and bloody blisters appeared, but the diuretics did not relieve her
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When the patient came to our hospital for treatment for the first time, he took losartan, sitagliptin, spironolactone, lubiprostone, vitamin B complex, and potassium gluconate
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Because it was suspected that dipeptidyl peptidase-4 inhibitor (DPP-4i) might induce bullous pemphigoid (BP) and edema, he was asked to stop sitagliptin, and other drugs remained unchanged
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One week after sitagliptin was stopped, the edema was significantly improved, no new blisters appeared, and the weight decreased from 62.
3 kg to 55.
5 kg (Figure 1B)
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In the subsequent follow-up, the patient's anti-bp180 antibody was negative, bullous pemphigoid (BP) was excluded, and the final diagnosis was edema and blisters caused by DPP-4i
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After 44 days of treatment, the patient's weight further dropped to 49.
0 kg, and the edema of the feet was significantly improved.
Although DPP-4i was stopped, blood glucose remained well controlled
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Figure 1 When a patient came to our hospital for the first time (A) and 1 week after stopping sitagliptin (B) DPP-4i-related skin adverse reactions, which patients are at higher risk? Although some cases have reported DPP-4i-related bullous pemphigoid or edema, this adverse reaction is really rare, and it can recover on its own after stopping the drug
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The overall safety of DPP-4i is good .

The mechanism by which DPP-4i induces the formation of vesicles has not been fully elucidated, and it is considered that the drug may trigger certain immune pathogenic reactions
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Through the analysis of DPP-4i-related BP cases, some scholars have found that this adverse reaction is related to the patient's own HLADQB1*03:01 gene, but it is still impossible to accurately distinguish based on the basic characteristics of the patient
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This case brings two enlightenments.
First, for unexplained rash and edema, drug-derived factors should be considered
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According to reports, a variety of drugs may cause skin-related adverse events
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Therefore, primary care physicians should be aware of all medication use in elderly patients, and should be vigilant against unexpected, non-specific adverse drug events, especially for new drugs with limited information on adverse reactions
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Secondly, the doctor should master the medication history of each drug in the patient to form a reasonable diagnosis hypothesis
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Usually as memory/intelligence declines, some elderly people may not be able to provide an accurate medical history and medication history
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Therefore, primary care physicians should focus on comprehensive cooperation with medical professionals and family members to obtain more comprehensive information for more accurate diagnosis and treatment
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Yimaitong compiled and compiled from: Maita H, Kobayashi T, Akimoto T, Osawa H, Kato H.
Severe edema and blood blisters of the lower extremities caused by sitagliptin, a dipeptidylpeptidase-4 inhibitor.
J Gen Fam Med.
2021;00: 1-2.