Hyperglycaemic hyperosmolar nonketotic syndrome; acute kidney injury; Community-acquired bacterial pneumonia; subjective fever; fatigue; myalgia; This literature-study case was reported in a literature article and describes the occurrence of HYPERGLYCAEMIC HYPEROSMOLAR NONKETOTIC SYNDROME (Hyperglycaemic hyperosmolar nonketotic syndrome ), ACUTE KIDNEY INJURY (acute kidney injury) and PNEUMONIA BACTERIAL (Community-acquired bacterial pneumonia) in a 59-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.   LITERATURE REFERENCE:     The patient's past medical history included COVID-19 (COVID-19 infection 10 months earlier). Concurrent medical conditions included Type 2 diabetes mellitus (history of T2DM of 8 years duration) and Hypertension (History of T2DM of 8 years duration, hypertension).    On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, the patient experienced HYPERGLYCAEMIC HYPEROSMOLAR NONKETOTIC SYNDROME (Hyperglycaemic hyperosmolar nonketotic syndrome ) (seriousness criteria hospitalization and medically significant), ACUTE KIDNEY INJURY (acute kidney injury) (seriousness criteria hospitalization and medically significant), PYREXIA (subjective fever), FATIGUE (fatigue), MYALGIA (myalgia) and PNEUMONIA BACTERIAL (Community-acquired bacterial pneumonia) (seriousness criteria hospitalization and medically significant). The patient was treated with METFORMIN at a dose of 1000 mg twice a day; SITAGLIPTIN at a dose of 100 mg once a day; INSULIN GLARGINE (GLARGINE BIOCON) for Hyperosmolar hyperglycemic syndrome, at a dose of 12 unit once a day; INSULIN LISPRO (LISPRO INSULIN) for Hyperosmolar hyperglycemic syndrome, at a dose of 6 unit once a day; SALINE [SODIUM CHLORIDE] for Hyperosmolar hyperglycemic syndrome, at a dose of 3 liter and INSULIN for Hyperosmolar hyperglycemic syndrome, at an unspecified dose and frequency. At the time of the report, HYPERGLYCAEMIC HYPEROSMOLAR NONKETOTIC SYNDROME (Hyperglycaemic hyperosmolar nonketotic syndrome ) and PYREXIA (subjective fever) outcome was unknown and ACUTE KIDNEY INJURY (acute kidney injury), FATIGUE (fatigue), MYALGIA (myalgia) and PNEUMONIA BACTERIAL (Community-acquired bacterial pneumonia) had resolved. Possible    DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood bicarbonate: 23 meq/l bicarbonate of 23 mEq/L. On an unknown date, Blood creatinine: 3.32 mg/dl the creatinine was 3.32 mg/dL. On an unknown date, Blood glucose: 847 mg/dl blood glucose of 847 mg/dL. On an unknown date, Blood lactate dehydrogenase: 616 (High) CRP and LDH were both elevated at 2109 mg/dL and 616 U/L, respectively. On an unknown date, Blood osmolarity: 345 mosm/kg the calculated serum osmolality was 345 mOsm/Kg. On an unknown date, Blood pressure normal: normotensive without tachycardia normotensive without tachycardia. On an unknown date, Blood sodium: 137 meq/l The sodium was 137 mEq/L. On an unknown date, Blood urea: 67 mg/dl BUN was 67 mg/dL. On an unknown date, Body mass index: 27.7 kg/m2 a BMI of 27.7 kg/m2.. On an unknown date, Body temperature normal: the patient remained afebrile the patient remained afebrile. On an unknown date, C-reactive protein: 2109 mg/dl (High) CRP and LDH were both elevated at 2109 mg/dL and 616 U/L, respectively. On an unknown date, Chest X-ray: right basal density a chest x-ray that showed a questionable right basal density. On an unknown date, Glycosylated haemoglobin: 7.5% A recent HbA1c from 8 weeks pre-admission was 7.5%, 13.2%. The repeat HbA1c during hospitalization was 13.2%. and 5.9% A repeat HbA1c of 5.9%. On an unknown date, Influenza A virus test: negative (Negative) There were no other signs of an infection, including a negative urinalysis and negative PCR swab tests for SARS-CoV-2, Influenza A and B, and RSV.. On an unknown date, Influenza B virus test: negative (Negative) There were no other signs of an infection, including a negative urinalysis and negative PCR swab tests for SARS-CoV-2, Influenza A and B, and RSV.. On an unknown date, Lymphocyte count: normal (normal) normal lymphocyte count. On an unknown date, Neutrophil count (1.8-7.7): 13 k/ul a neutrophilia of 13 k/uL (RR, 1.8-7.7 K/ uL). On an unknown date, Oxygen saturation: >96 % >96% oxygen saturation on room air.. On an unknown date, Physical examination: significant The physical exam was significant for a fully alert and oriented mental status, dry oral mucosa, clear lungs, a non-tender and non-distended abdomen.. On an unknown date, Respiratory syncytial virus test: negative (Negative) There were no other signs of an infection, including a negative urinalysis and negative PCR swab tests for SARS-CoV-2, Influenza A and B, and RSV.. On an unknown date, SARS-CoV-2 test: negative (Negative) Negative. On an unknown date, Troponin: negative (Negative) The troponins were negative. On an unknown date, Urine analysis: negative (Negative) There were no other signs of an infection, including a negative urinalysis. On an unknown date, Urine ketone body: 15 mg/dl urine ketones were mildly elevated at 15 mg/dL. On an unknown date, Vital signs measurement: stable his vital signs were stable. On an unknown date, White blood cell count (4.8-10.8): 16.7 k/ul Due to a mild leukocytosis of 16.7 k/uL (RR, 4.8- 10.8 k/uL). On an unknown date, pH body fluid: 7.39 pH of 7.39.     The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered HYPERGLYCAEMIC HYPEROSMOLAR NONKETOTIC SYNDROME (Hyperglycaemic hyperosmolar nonketotic syndrome ), ACUTE KIDNEY INJURY (acute kidney injury), PYREXIA (subjective fever), FATIGUE (fatigue), MYALGIA (myalgia) and PNEUMONIA BACTERIAL (Community-acquired bacterial pneumonia) to be possibly related.    No relevant concomitant medications were reported.  He denied cough, dyspnea, rhinorrhea, abdominal pain, diarrhea, nausea, or dysuria. The patient was empirically treated for a community-acquired bacterial pneumonia. A repeat HbA1c of 5.9% and a C-peptide of 6.02 ng/mL 2 months after discharge indicated complete resolution of the prior hyperglycemic emergency. The patient was discharged home on a simplified regimen of glargine 12 units once daily, metformin 1000 mg twice daily, and sitagliptin 100 mg daily. The patient's glycemic control improved at home with glucoses consistently ranging less than 140 mg/dL and the regimen has since been gradually downtitrated to merely metformin 1000 mg twice daily.A recent HbA1c from 8 weeks pre-admission was 7.5%, for which the patient was not taking any T2DM medications.  This case concerns a 59-year-old, male patient with a history of Type 2 diabetes mellitus and COVID-19 infection (10 months earlier), who experienced the unexpected serious events of Hyperglycaemic hyperosmolar nonketotic syndrome, Pneumonia bacterial and Acute kidney injury (AESI). The events occurred approximately 2 days after the first dose of mRNA-1273 vaccine. The rechallenge was unknown since the events happened after the first dose and no information on additional dosing is available. The medical history of Type 2 diabetes mellitus and COVID-19 infection (10 months earlier) remain as confounders. Acute kidney injury could be a result of Hyperglycaemic hyperosmolar nonketotic syndrome. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. Case was assessed as serious due to important medical event and hospitalization.   This case was linked to MOD-2021-394130 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 24-Nov-2021: Follow up received by safety on 25-Nov-2021 included an Email with Agency received from medical team includes medical history, lab data, events, patient details.; Sender's Comments: This case concerns a 59-year-old, male patient with a history of Type 2 diabetes mellitus and COVID-19 infection (10 months earlier), who experienced the unexpected serious events of Hyperglycaemic hyperosmolar nonketotic syndrome, Pneumonia bacterial and Acute kidney injury (AESI). The events occurred approximately 2 days after the first dose of mRNA-1273 vaccine. The rechallenge was unknown since the events happened after the first dose and no information on additional dosing is available. The medical history of Type 2 diabetes mellitus and COVID-19 infection (10 months earlier) remain as confounders. Acute kidney injury could be a result of Hyperglycaemic hyperosmolar nonketotic syndrome. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. Case was assessed as serious due to important medical event and hospitalization.