Acute quadruple extremity compartment syndrome due to angio-oedema after polypharmacy overdose including olmesartan medoxomil, telmisartan and vildagliptin.

This case report describes a rare manifestation of acute compartment syndrome (ACS) involving all four extremities, precipitated by angio-oedema in a middle-aged woman who consumed an overdose of multiple medications: nifedipine, azelnidipine, amlodipine besylate, olmesartan medoxomil, telmisartan, esaxerenone and vildagliptin. She presented with haemodynamic instability, necessitating intubation. Despite stabilising haemodynamic parameters within 24 hours, she manifested escalating extremity oedema. At 52 hours after ingestion, mottled skin was observed, along with necrotic alterations in the swollen hands and compartment pressures exceeding 30 mm Hg in all extremities. ACS was diagnosed, leading to fasciotomies. The aetiology is postulated to be drug-induced angio-oedema, possibly intensified by the concurrent overdose of olmesartan medoxomil, telmisartan and vildagliptin, each of which has a risk of angio-oedema even at standard dosages. This scenario is a very rare case caused by drug-induced angio-oedema, which underscores the importance of vigilant monitoring to detect ACS in patients with progressing limb oedema.

Dipeptidyl Peptidase-4 Inhibitor-Related Bullous Pemphigoid: Clinical, Laboratory, and Histological Features, and Possible Pathogenesis.

Dipeptidyl peptidase-4 inhibitor (DPP4i) is a widely used antidiabetic agent. Emerging cases of DPP4i-associated bullous pemphigoid (DBP), whose pathogenesis remains unclear, have been reported. Thus, a retrospective study was conducted from January 2016 to June 2021 to determine the clinical, laboratory, and histopathological features of DBP and idiopathic bullous pemphigoid (IBP). We set up in vitro experiments using vildagliptin-treated HaCaT keratinocytes to validate what we found by analyzing published RNA sequencing data about the genes related to the dermal-epidermal junction. We also observed IL-6 expression by HaCaT cells treated with vildagliptin. We enrolled 20 patients with DBP and 40 patients with IBP. The total Bullous Pemphigoid Disease Area Index (BPDAI) score was similar in both groups. However, the BPDAI score of erosions and blisters in DBP was significantly higher than that in IBP (24.6 vs. 16.68, p = 0.0189), and the score for urticaria and erythema was lower in DBP (12 vs. 19.05, p = 0.0183). The pathological features showed that the mean infiltrating eosinophil number per high-power field was significantly lower in DBP than in IBP (16.7 vs. 27.08, p = 0.023). The expression of LAMA3, LAMB3, LAMC2, DST, and COL17A1 decreased significantly in vildagliptin-treated human keratinocytes. On the other hand, IL-6, the hallmark cytokine of bullous pemphigoid (BP) severity, was found to be upregulated in HaCaT cells by vildagliptin. These experimental findings imply less of a requirement for eosinophil infiltration to drive the inflammatory cascades in DBP blistering. Both immunologic and non-immunologic pathways could be employed for the development of DBP. Our findings may help explain the higher incidence of non-inflammatory BP that was observed in DBP.

The association of bullous pemphigoid with dipeptidyl-peptidase 4 inhibitors: a ten-year prospective observational study.

BACKGROUND: Bullous pemphigoid is the most common bullous chronic autoimmune skin disease. Recent studies have suggested dipeptidyl-peptidase 4 inhibitors as possible predisposing agents of bullous pemphigoid. The objective of our study was to prospectively estimate the association between gliptins and the development of bullous pemphigoid. METHODS: We conducted a prospective study which included all patients diagnosed with biopsy-proven bullous pemphigoid in the Dermatology Department of our hospital between April 1, 2009 and December 31,2019. The diagnosis of bullous pemphigoid was based on specific clinical, histological and immunological features. RESULTS: Overall 113 consecutive patients (age 75 ± 13 years, 62 females) with the diagnosis of bullous pemphigoid were enrolled. Seventy-six patients (67.3%) suffered from type 2 Diabetes and 52 (46%) were treated with dipeptidyl-peptidase 4 inhibitors. The most frequent prescribed gliptin was vildagliptin, being administered to 45 cases (39.8% of total patients enrolled, 86.5% of the patients treated with gliptins). Gliptins were withdrawn immediately after the diagnosis of bullous pemphigoid, which together with steroid administration led to remission of the rash. CONCLUSIONS: This study revealed that treatment with dipeptidyl-peptidase 4 inhibitors, especially vildagliptin, is significantly associated with an increased risk of bullous pemphigoid development.

A case of anti-BP230 antibody-positive bullous pemphigoid receiving DPP-4 inhibitor.

Bullous pemphigoid (BP) is a cutaneous autoimmune blistering disorder. Recently, it has been reported that dipeptidyl peptidase-4 inhibitors (DPP4i) is associated with the development of BP (DPP4i-BP). Patients with DPP4i-BP have autoantibodies (autoAbs) preferentially targeting full-length BP180, but not the BP180NC16a domain. In this report, we described a case of anti-BP230 antibody (Ab)-positive BP receiving DPP4i. A 78-year-old male with a medical history of type 2 diabetes receiving vildagliptin at 100 mg daily for 38 months was referred to our hospital with itching blisters on his body and extremities. Skin biopsy showed subepidermal bulla with eosinophil infiltration. Direct immunofluorescence staining revealed a linear staining pattern with complement C3 and IgG at the subepidermal basement membrane zone. By laboratory testing, autoAbs against BP180NC16a and full-length BP180 were negative by enzyme-linked immunosorbent assay (ELISA); however, anti-BP230 Abs were positive by ELISA (index: 123.91). His HLA genotype was DQB1*04:01 and 05:01. Based on these results, we diagnosed the patient with anti-BP230 Abs-positive BP associated with DPP4i. To the best of our knowledge, this is the first case of DPP4i-BP with only anti-BP230 Abs. Further accumulation of DPP4i-BP cases is needed to clarify the relationship between overall features of DPP4i-BP and anti-BP230 Abs.

Reprotoxic activities of vildagliptin administration in male Wistar rats

Vildagliptin is an oral hypoglycemic agent used in the management of diabetes. Some oral antidiabetic drugs have been implicated in reproductive toxicity.The objective of this study was to investigate the effects of daily administration of vildagliptin at different dosages (0.35 mg/kg B.W., 0.70 mg/kg B.W. and 1.40 mg/kg B.W.) to male Wistar rats for 8 weeks. Sperm parameters, serum concentrations of testosterone, follicle stimulating hormone and luteinizing hormone and the histology of the testis of the rats were assessed. Another set of rats were also treated for 8 weeks and allowed to recover and the same parameters were assessed in them. Fertility study was conducted by determining their litter size. The results showed that vildagliptin administration significantly reduced sperm count and motility of the treated rats. It also significantly increased the number of abnormal sperms. Serum level of testosterone was significantly decreased while luteinizing hormone and follicle stimulating hormone levels showed no significant change. The histoarchitecture of the testis of the treated rats appeared visibly normal. The litter size was also significantly reduced. Most of the changes observed were dose dependent. However, these parameters were restored towards normal in the recovery group. Our results suggest that vildagliptin adversely affected sperm parameters, affected litter size and disrupted the pituitary - gonadal axis. These changes were however reversed upon cessation of drug administration.

Dipeptidyl peptidase 4 inhibitors linked bullous pemphigoid in patients with type 2 diabetes mellitus: A series of 13 cases.

BACKGROUND: Dipeptidyl peptidase 4 (DPP4) inhibitors have increasingly been linked to bullous pemphigoid, but there is paucity of data from India where about 1.85 million patients have been estimated to use these drugs. METHODS: In 30,000 patients with T2DM seen by us in two tertiary care centres since 2015, we detected 13 cases of bullous pemphigoid linked to DPP4 inhibitors. We used WHO-UMC (World Health Organisation-Uppsala Monitoring Centre) causality assessment system for assessment. RESULTS: Lesions of bullous pemphigoid appeared at varied intervals (within 1 weeks-2 years) after start of DPP4 inhibitors. Implicated drugs were Linagliptin (n, 8), Vildagliptin (n, 4) and Sitagliptin (n, 1). Mostly, lesions were seen after 60 years age, and over trunk and extremities. Skin biopsy was compatible with bullous pemphigoid in two patients. Lesions regressed within a month of stopping DPP4 inhibitors in 9 patients while delayed regression up to 6 months in 4 patients. Overall, skin lesions remitted in all patients and did not recur. CONCLUSION: Any new bullous lesion appearing while patient is on DPP4 inhibitors should be considered as bullous pemphigoid and should necessitate prompt withdrawal of the drug.

Vildagliptin-induced ground-glass nodules mimicking lung metastases in a cancer patient receiving Lactobacillus probiotic supplementation.

The association between gut microbiota and the lung immune system has been attracting increasing interest. Here, we report a case of pancreatic cancer in which the dipeptidyl peptidase-4 inhibitor vildagliptin induced unusual manifestations of interstitial pneumonia, possibly under the influence of Lactobacillus paraplantarum probiotic supplementation. Chest computed tomography and positron emission tomography showed multiple ground-glass nodules (GGNs) mimicking metastatic lung cancer. Transbronchial biopsy specimens showed mild fibrosis and infiltration of lymphocytes consisting of more CD4+ than CD8+ cells. The CD4+ cells did not include FOXP3+ regulatory T cells. Bronchoalveolar lavage confirmed lymphocytosis with a markedly increased CD4+ /CD8+ ratio of 7.4. The nodules disappeared shortly after vildagliptin and probiotics were withheld. If unusual interstitial pneumonia is observed in some cancer patients, physicians should pay careful attention to their medication history, including probiotic supplements.

Dipeptidyl Peptidase-4 Inhibitor-Associated Bullous Pemphigoid.

Bullous pemphigoid (BP) is an organ-specific autoantibody-mediated blistering skin disease that mainly affects the elderly. Typical clinical features include the widespread blisters, often preceded by and/or associated with itchy urticarial or eczema-like lesions. BP patients have circulating autoantibodies against BP180 and/or the plakin family protein BP230 both of which are components of hemidesmosomes in basal keratinocytes. Most BP autoantibodies particularly target the epitopes within the non-collagenous NC16A domain of BP180. Clinical findings and murine models of BP have provided evidence of a pathogenic role of anti-NC16A autoantibodies. However, it is largely unknown what triggers the breakage of immunotolerance against BP180 in elderly individuals. The incidence of BP has been increased over the past two decades in several countries. Aside from aging populations, the factors behind this phenomenon are still not fully understood. Neurodegenerative diseases such as multiple sclerosis, Parkinson's disease, and certain dementias are independent risk factors for BP. Recently several case reports have described BP in patients with diabetes mellitus (DM) patients who have been treated with dipeptidyl peptidase-4 inhibitors (DPP-4i or gliptins), which are a widely used class of anti-DM drugs. The association between the use of DPP-4is, particularly vildagliptin, and BP risk has been confirmed by several epidemiological studies. Evidence suggests that cases of gliptin-associated BP in Japan display certain features that set them apart from cases of "regular" BP. These include a "non-inflammatory" phenotype, targeting by antibodies of different immunodominant BP180 epitopes, and a specific association with the human leukocyte antigen (HLA) types. However, recent studies in European populations have found no major differences between the clinical and immunological characteristics of gliptin-associated BP and "regular" BP. The DPP-4 protein (also known as CD26) is ubiquitously expressed and has multiple functions in various cell types. The different effects of the inhibition of DPP-4/CD26 activity include, for example, tissue modeling and regulation of inflammatory cells such as T lymphocytes. Although the pathomechanism of gliptin-associated BP is currently largely unknown, investigation of the unique effect of gliptins in the induction of BP may provide a novel route to better understanding of how immunotolerance against BP180 breaks down in BP.

Identification of Novel Metabolites of Vildagliptin in Rats: Thiazoline-Containing Thiol Adducts Formed via Cysteine or Glutathione Conjugation.

Vildagliptin (VG), a dipeptidyl peptidase-4 inhibitor, is used for treating type 2 diabetes. On rare occasions, VG causes liver injury as an adverse reaction. One case report suggested the involvement of immune responses in the hepatotoxicity, but the underlying mechanisms are unknown. We recently reported that VG binds covalently in vitro to l-cysteine to produce a thiazoline acid metabolite, M407, implying that the covalent binding may trigger the immune-mediated hepatotoxicity. There was no evidence, however, that such a thiazoline acid metabolite was formed in vivo. In the present study, we administered a single oral dose of VG to male Sprague-Dawley rats, and detected M407 in plasma. The sum of urinary and fecal excretions of M407 reached approximately 2% of the dose 48 hours postdosing. Using bile duct-cannulated rats, we demonstrated that M407 was secreted into bile as a glucuronide, designated as M583. Another newly identified thiazoline metabolite of VG, the cysteinylglycine conjugate M464, was detected in urine, feces, and bile. The formation of M464 was confirmed by in vitro incubation of VG with glutathione even in the absence of metabolic enzymes. A glutathione adduct against the nitrile moiety M611 was also detected in vitro but not in vivo. In summary, we found three new thiazoline-containing thiol adduct metabolites in VG-administered rats. Nonenzymatic covalent binding of VG would likely occur in humans, and it may be relevant to predicting adverse reactions.

The Role of Vildagliptin in Treating Hypertension Through Modulating Serum VEGF in Diabetic Hypertensive Patients.

BACKGROUND: Several trials have reported that dipeptidyl peptidase-4 (DPP-4) inhibitors are used to improve endothelial function in addition to treating type 2 diabetes (T2DM). The current study investigated the effects of vildagliptin, DPP-4 inhibitor, compared to metformin on endothelial function and blood pressure through vascular endothelial growth factor (VEGF) modulation in patients with T2DM and hypertension. METHODS: This study was designed as a randomized controlled parallel study. A total of 120 volunteers were recruited and allocated into 4 groups: healthy volunteers, patients recently diagnosed with hypertension and diabetes, patients treated with captopril for hypertension in addition to metformin, and patients treated with captopril in addition to vildagliptin. The percentage change in body weight was calculated in addition to serum VEGF levels, blood pressure, glycated hemoglobin (HbA1c), total lipid profile, and insulin resistance. RESULTS: At the end of the therapeutic period, the results showed that vildagliptin significantly decreased blood pressure and increased serum VEGF levels, while metformin was more effective at lowering body weight. In comparison with metformin, vildagliptin showed a promising action through its antihypertensive effect via elevating VEGF levels and improving physiological angiogenesis and vasculature. WHAT IS NEW AND CONCLUSION: Vildagliptin showed a promising action through its blood pressure-regulating effect via modulating VEGF levels and improving physiological angiogenesis and vasculature, in addition to improving the lipid profile of patients, while metformin was better in reducing body weight.

CMD-05, a novel promising clinical anti-diabetic drug candidate, in vivo and vitro studies.

Dipeptidyl peptidase IV (DPP-IV) inhibitor has been expected to be a new class of anti-diabetic agent. The present study was designed to characterize the pharmacological profiles of CMD-05, a novel DPP-IV inhibitor discovered in our laboratory, in vitro and in vivo. The IC50 of CMD-05 on DPP-IV inhibitory activity was approximately 12 nM while vildagliptin was 3.5 nM in vitro. In diabetes rat model established by high fat diet/low dose streptozotocin, CMD-05 inhibited DPP-IV activity, significantly improved glucose tolerance, increased GLP-1 and insulin levels in plasma. Long-term administration of CMD-05 decreased HbA1c and TG levels and improved the islet function without significantly effect on body weight. Furthermore, CMD-05 reduced INS-1 cell apoptosis and increased GLP-1 secretion in NCI-H716. After oral administration, CMD-05 reached peak concentration at 30 min with half-life of 288 minutes and the inhibitory rate of DPP-IV greater than 50% lasted for 15 h. In fasted normal rats, CMD-05 didn't cause significant hypoglycemia. CMD-05 had a lower cytotoxicity than vildagliptin in vitro and its maximum tolerance dose in mice is beyond 2000 mg/kg. These results indicated that CMD-05 has similar activity with vildagliptin in vivo and has a much longer half-life and lower cytotoxicity than vildagliptin.