CASE REPORT e-ISSN: 2349-0659 p-ISSN; 2350-0964 Coronavirus Disease-19 Pneumonia or Pneumocystis carinii Pneumonia in a Patient with Diabetes: A Diagnostic Dilemma Ayan Banerjee 1 , Pradipta Bhatacharya 1 , Hironmoy Roy 1 , Sukanta Sen 2 A BSTRACT Coronavirus disease 2019 (COVID‐19) and pneumocystis pneumonia share many overlapping features and may be clinically indistinguishable on initial presentation in people living with human immunodefciency virus severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) belongs to the subfamily of beta-coronavirus, which are responsible for respiratory, enteric, hepatic, and neurologic diseases, due to their broad tissue tropism. In the present patient, the course was acute with dyspnea being one of the major symptoms and lung involvement was seen to be peripheral. The two negative reverse transcription polymerase chain reaction (RT-PCR) reports for SARS-CoV-2 along with the diferences in the interpretation of the computed tomography scans led to the diagnosis difculty in the present case. COVID-19 pneumonia may have similar presentation like that of Pneumocystis carinii pneumonia. The low sensitivity of RT-PCR which is considered the gold standard of diagnosis of SARS-CoV-2 and the similarities in presentation between the two types of pneumonia, along with increased prevalence of both the types of pneumonia amongst diabetics, may give rise to diagnostic difculties. Keywords: Coronavirus disease 2019, Coronavirus disease-19 pneumonia, High-resolution computed tomography of thorax, Pneumocystis carinii pneumonia, Reverse transcription polymerase chain reaction, Severe acute respiratory syndrome-coronavirus 2, Type 2 diabetes mellitus Asian Pac. J. Health Sci., (2021); DOI: 10.21276/apjhs.2021.8.3.03 ©2021 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (http:// creativecommons.org/ licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. C ASE R EPORT A 75-year-old male with a history of type 2 diabetes mellitus for the past 10 years on oral hypoglycemic agents along with a history of ischemic heart disease presented to the emergency department with complaints of dyspnea on exertion and shortness of breath for the past 7 days, decreased urine output for the past 2 days and pain in the left lower limb. The patient had been admitted at his local hospital where a reverse transcription polymerase chain reaction (RT-PCR) test for severe acute respiratory syndrome- coronavirus 2 (SARS-CoV2) was found to be negative and he was given treatment with bronchodilators, diuretics, and antibiotics for 2 days without any improvement in symptoms. On examination, he was conscious and oriented. He had tachycardia (140/min), was normotensive (140/80 mmHg). There was bilateral crepitation on chest examination. Examination of all the other systems was found to be normal. Investigations Following are the results of the investigations done: • Hypoxia in arterial blood gas analysis with oxygen saturation of 93% without oxygen • Total leukocyte count was raised (18,000/mm 3 ) with a left shift (neutrophil count: 93%, lymphocyte count: 7%) • Random blood sugar at admission: 260 mg/dL • Glycosylated hemoglobin: 9.5% • Creatinine: 1.5 mg/dL • Blood urea: 65 mg/dL. Infammatory parameters were as follows: • C-reactive protein: 20.8 mg/dL • Lactate dehydrogenase (LDH): 638 U/L • D-dimer: 2231 DDU • Ferritin: 586 ng/mL • Procalcitonin: 0.4 ng/mL 1 Department of Critical Care Medicine, Neotia Getwel Healthcare Centre, Siliguri, West Bengal, India, 2 Department of Pharmacology, ICARE Institute of Medical Sciences and Research, Haldia, West Bengal, India Corresponding Author: Dr. Sukanta Sen, Department of Pharmacology, ICARE Institute of Medical Sciences and Research, Banbishnupur, Purba Medinipur, Haldia - 721 645, West Bengal, India. E-mail: drsukant@gmail.com How to cite this article: Banerjee A, Bhattacharya P, Roy H, Sen S. Coronavirus Disease-19 Pneumonia or Pneumocystis carinii Pneumonia in a Patient with Diabetes: A Diagnostic Dilemma. Asian Pac. J. Health Sci., 2021; 8(3):15-17 Source of support: Nil Conficts of interest: None. Received: 23/03/2021 Revised: 25/04/2021 Accepted: 13/05/2021 • Interleukin-6: 6.2 pg/mL • Troponin I: Negative • Liver function test was normal • Urine and blood culture/sensitivity were not suggestive of any infections, were sterile • Left lower limb venous Doppler revealed complete obstruction of the venous system • Multiplex polymerase chain reaction (BioFire) from nasopharyngeal swab was negative. High-resolution computed tomography (HRCT) of thorax was done twice 3 days apart which had entirely diferent interpretations from two diferent radiologists: The frst HRCT of thorax revealed multiple areas of ground-glass opacity with small patches of consolidation and inter/intraseptal thickening in all segments of both lungs, more predominant in the peripheral lung and multiple rounded air cysts with a computed tomography (CT) severity index of 23/25, suggestive of coronavirus disease (COVID)-19 pneumonia [Figure 1a]. A second RT-PCR for