We would like to share ideas on the publication “A case of acute interstitial nephritis following the Pfizer-BioNTech COVID-19 vaccine.1” Flor Merino et al. reported a case and discussed on possible pathophysiological interrelationship. The COVID-19 vaccine can induce several atypical clinical adverse event and acute interstitial nephritis might be a possible one. However, it is necessary to recognize that there are other confounding factors that might result in the observed clinical problem. Without a complete laboratory investigation at pre-vaccination stage, it cannot rule out background medical problem. Also, the concurrent medical problem can occur in a COVID-19 vaccine recipient and might result in a renal problem. A good example is the concurrent dengue infection.2

Additionally, the patient might have prior or concurrent asymptomatic COVID-19 that can alter the immune response to the vaccine. Since asymptomatic COVID-19 is not uncommon and can be easily missed,3 the exact conclusion on the present case is still not final. It is necessary to have a complete investigation before a final conclusion.