Although there are few reported cases of pembrolizumab induced new onset DKA in a non diabetic patients due to its autoimmune nature, its association in worsening glycemic control and DKA in pre-existing type 2 Diabetes mellitus is not well established.
CASE 79 years old female with past medical hx of DM type 2 (Hba1c 7.4 was started on metformin), COPD(on chronic steroids and trilogy machine at home), recently diagnosed with poorly differentiated adenocarcinoma of the left lung, metastasis to liver, PDL 1 positive at 99%, started on palliative chemotherapy with Keytruda, 2 weeks after the third cycle of keytruda presented to the ED for AMS. Patient noted to be very dehydrated, somnolescent and tachypnea. Labs consistent with sugars > 600, potassium 6.8, Bicarb 5, Anion gap 33, beta hydroxybutyrate 11.5 (on 7/15/19 0.6), HbA1c 9.7,(On 12/15/16 7.3, 9/25/18 6.7, 1/22/19 7.4). PH 7.31, lactate 2.4. WBC count 21.5- no infectious source identified (CXR, CT brain, UA clean). Patient was admitted for DKA and treated with IV insulin and IV fluids. After medically stable patient was discharged with Insulin regimen. Within 5 days after being discharged, patient presented to ED again with DKA with PH 7.27, Bicarb 8, anion gap 22, sugars>600, beta hydroxybuterate 13.70. Patient was Rx for DKA- after a week of hospitalization was discharged to Hospice(due to metastatic cancer) and few weeks later expired.To summarize, pt with well controlled type 2 DM on metformin presented with frequent DKA 2 weeks after treatment with third cycle of keytruda leading to worsening glycemic control in-turn making patient Insulin dependent.
CONCLUSION Incidence of Type 1 DM with pembrolizumab treatment is being increasingly recognized and reported, and DKA is a common initial presentation. However we need further studies to establish the mechanism of worsening glycemic control leading to Insulin dependent and DKA in patients with pre-existing type 2 diabetes.
REFERENCES Immune checkpoint inhibitors and type 1 diabetes mellitus: a case report and systematic review Jeroen M K de Filette1, Joeri J Pen2, Lore Decoster3, Thomas Vissers4, Bert Bravenboer1, Bart J Van der Auwera5, Frans K Gorus5, Bart O Roep6,7, Sandrine Aspeslagh3, Bart Neyns3, Brigitte Velkeniers1 and Aan V Kharagjitsingh1,2,5,8