DPP4-Inhibitor Drug-Induced Bullous Pemphigoid

The patient is a 68 yo woman with Type II diabetes and Stage IV renal failure who presented with a four month history of intense generalized pruritus.  Her PCP had treated her for scabies without effect.  Her medications  include Lantus, lisinopril, atorvastin risperadone  and Januvia (sitaglipin).  The Januvia was the  most recent new medication and it was started a month or two before she started to itch.

O/E:  there was a wide-spread dermatitis on torso and extremities.  No frank bullae but there was a suggestion of vesicles.  No burrows were seen.  Vesicles were noted on the palms and soles.

An eliptical biopsy was done as well as a 3 mm punch biopsy from perilesional skin for DIF.

Histopath showed: Eosinophilic spongiosis and spongiotic vesiculation.
DIF was positive for IgG in a linear pattern at the DEJ
Histological Photographs courtesy of Dr. Jag Bhawan, Boston University SkinPath Laboratory

Diagnosis:  Bullous Pemphigoid secondary to DPP-4 inhibitor.  

Discussion: DPP-4 inhibitors  are a class of drugs that are used for Type 2 diabetes.  There have been eight references to BP as a cutaneous drug effect DPP-4 inhibitors in PubMed (the first was in 2016).  It is clear that we will be seeing more of these patients what with the wide-spread usage of DPP-4 inhibitors.

Acknowledgement:  Special thanks to Rick Sontheimer, M.D. who alerted me to this phenomenon and Dr. Jag Bhawan for the pathology interpretation and the beautiful photomicrographs.

References:

 1. Bullous Pemphigoid Associated with the Dipeptidyl Peptidase-4 Inhibitor Sitagliptin in a Patient with Liver Cirrhosis Complicated with Rapidly Progressive Hepatocellular Carcinoma. Harada M et. al.  Intern Med. 2017 Sep 15;56(18):2471-2474  Free Ful Text. 

2. Dipeptidyl peptidase IV inhibitors, a risk factor for bullous pemphigoid: Retrospective multicenter case-control study from France and Switzerland.  Benzaquen M, det. Al.. J Am Acad Dermatol. 2018 Jun;78(6):1090-1096

CONCLUSIONS: DPP4is, especially vildagliptin, are associated with an increased risk for development of BP. Their use needs to be carefully evaluated, particularly in high-risk patients, such as males and those age 80 years or older.  Full Abstract.

3. Vildagliptin significantly increases the risk of bullous pemphigoid: A Finnish nationwide registry study. O. Varpuluoma et. al. J. Invest Dermatol:

Volume 138, Issue 5, Supplement, Page S46, 2018.  Full Abstract (Supplied by Rick Sontheimer)