scleroderma renal crisis following MRNA COVID-19 vaccination; This is a literature report.  A 50-year-old female patient received COVID-19 Vaccine - Manufacturer Unknown, as dose 1, single (unknown manufracturer) (Batch/Lot number: unknown) for 1 day for covid-19 immunisation. The patient's relevant medical history included: "mixed connective tissue disorder" (unspecified if ongoing); "worsening dyspnea" (unspecified if ongoing); "numbness" (unspecified if ongoing); "weakness of both lower extremities" (unspecified if ongoing); "acute kidney injury" (ongoing); "scleroderma renal crisis" (ongoing). Concomitant medication(s) included: MYCOPHENOLATE MOFETIL taken for scleroderma renal crisis. The following information was reported: SCLERODERMA RENAL CRISIS (hospitalization, medically significant, life threatening), 2 days after the suspect product(s) administration, outcome "unknown", described as "scleroderma renal crisis following MRNA COVID-19 vaccination". The patient underwent the following laboratory tests and procedures: Antinuclear antibody: Positive; Blood bicarbonate: 8 mEq/l; 10 mEq/l; Blood creatinine: 2.6 mg/dl; 1.6 mg/dl, notes: 4 months ago; Blood lactic acid: 10 mmol/L; Blood pressure measurement: 230/127 mmHg, notes: elevated; 270/160 mmHg; Blood pressure improved; Brain natriuretic peptide: 25500 pg/mL; Computerised tomogram abdomen: negative for bowel ischemia; Computerised tomogram thorax: showed bilateral infiltrates and no pulmonary, notes: emboli; Culture: Negative; Echocardiogram: showed severe concentric left ventricular, notes: hypertrophy; Ejection fraction: 35 %; Haemoglobin: 7.4 g/dl; bronchoalveolar lavage fluid for viral: Negative; Laboratory findings: revealed severe metabolic acidosis; pH body fluid: 7.17; Physical examination: revealed cold lower extremities, a distended, notes: abdomen, and arthritic changes in both hands; Platelet count: 258 x10 3/mm3; SARS-CoV-2 test: Negative; Troponin: 0.4 ng/ml; Ultrasound scan: compatible with medical renal disease; White blood cell count: 23 x10 3/mm3. Therapeutic measures were taken as a result of scleroderma renal crisis. Case report: A 50-year-old female with a history of mixed connective tissue disorder with positive ANA titer, speckled pattern 1:1280, and  pindle apparatus pattern 1:640, presented with worsening dyspnea, numbness, and weakness of both lower extremities. Two days prior she received the first dose of COVID-19 mRNA vaccine and later developed nausea, vomiting, diarrhea, and anorexia. In the emergency department, patient was found to have an elevated blood pressure of 230/127 mmHg. Physical examination revealed cold lower extremities, a distended abdomen, and arthritic changes in both hands. Laboratory findings revealed severe metabolic acidosis with a pH of 7.17 and bicarbonate of 8 mEq/l. COVID-19 test was negative. Computed tomography (CT) of the chest showed bilateral infiltrates and no pulmonary emboli. CT of the abdomen was negative for bowel ischemia. Within a few hours, she developed agonal breathing and bradycardia of 30. Patient had pulseless electrical activity requiring resuscitation and hypothermia protocol initiation. Repeat chemistry showed lactate,10 mmol/l; WBC,23x10E3/ul; hemoglobin, 7.4 g/dl; platelets, 258x10E3/ul; bicarbonate, 10 mEq/l; increased creatinine, 2.6mg/dl from baseline 1.6mg/dl 4 months ago; troponin, 0.4 ng/ml; BNP, 25,500 pg/mL. Echocardiography showed severe concentric left ventricular hypertrophy with an ejection fraction of 35%, moderate diastolic dysfunction, and moderate pulmonary hypertension. Renal ultrasound was compatible with medical renal disease. Patient received aggressive IV fluid resuscitation, broad-spectrum antibiotics, and bicarbonate drip. Blood pressure remained elevated at 270/160 mmHg and she was started on IV enalapril 0.625mg every 6 hours with titration up to 2.5mg. Blood pressure improved further with nicardipine drip initiation and transition to captopril 25mg orally every 8 hours. During hospitalization infectious workup was negative, and bronchoalveolar lavage fluid for viral and fungal cultures was negative for opportunistic infections. Mycophenolate was resumed. Patient was successfully extubated on day 6. Discussion: COVID-19 vaccination is recommended for the general population with acceptable side effects following the vaccine, including myalgia, headache, fever, and nausea. In a recent literature review, 46 cases of various renal complications following COVID-19 vaccination are reported. COVID-19 vaccines became known to trigger a new onset or relapse of various glomerular diseases due to potent immune dysregulation. Here we describe a case of scleroderma renal crisis following COVID-19 vaccination. Conclusions: Our patient presented with hypertensive emergency along with acute kidney injury which was consistent with a scleroderma renal crisis. Inflammatory and immune responses triggered by mRNA COVID -19 vaccination could have potentially contributed to the vascular endothelial injury in kidney vasculature. Larger studies for this specific population would help to understand the effects of the immune mechanisms of COVID-19 vaccine and the importance of monitoring vascular complications for these patients following vaccination.; Sender's Comments: Based on the information provided, a causal relationship between BNT162b2 and the reported event scleroderma renal crisis cannot be excluded.  The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to regulatory authorities, Ethics Committees, and Investigators, as appropriate.