DIPLEGIA; ANAL INCONTINENCE; URINARY INCONTINENCE; ASTHENIA; ILIAC ARTERY EMBOLISM; ILIAC ARTERY OCCLUSION; PERIPHERAL ARTERY OCCLUSION; PERIPHERAL ARTERY STENOSIS; PERIPHERAL ARTERIAL OCCLUSIVE DISEASE; PERIPHERAL ARTERY THROMBOSIS; POOR PERIPHERAL CIRCULATION; ANGIOGRAM PERIPHERAL ABNORMAL; COMPUTERISED TOMOGRAM ABDOMEN; COMPUTERISED TOMOGRAM PELVIS ABNORMAL; BACK PAIN; This spontaneous report received from a health care professional via a Regulatory Authority VAERS (Vaccine Adverse Event Report System) concerned a 71 year old male of unspecified race and ethnicity. The patient's height, and weight were not reported. The patient's concurrent conditions included diabetes type II. The patient experienced drug allergy when treated with acetylsalicylic acid (aspirin), and ibuprofen.  The patient received Covid-19 vaccine ad26.cov2.s (suspension for injection, intramuscular, batch number: 1805020, expiry: unknown) dose was not reported, 1 total administered to left arm, on 18-MAR-2021 for prophylactic vaccination. Concomitant medications included ascorbic acid/calcium/minerals NOS/retinol/tocopheryl acetate/vitamin B NOS/vitamins NOS/zinc (centrum silver), fish oil, glipizide and lisinopril, all for unknown indications. Patient had acute onset of low back pain 1.5 weeks prior to presentation on 03-JUN-2021. On 09-JUN-2021, this pain and weakness (asthenia) progressed to complete bilateral lower extremity paralysis (diplegia) with loss of bowel function (anal incontinence) and bladder function (urinary incontinence). He was seen emergently and was found to have critical, bilateral lower extremity ischemia. Computerised Tomogram angiography of the abdomen and pelvis revealed: 1. Right runoff: abrupt vessel cut off suggestive of acute thrombotic occlusion of the proximal common femoral artery with propagation into the superficial femoral artery and the popliteal artery. On the delayed imaging a small amount of contrast was seen within the severely stenotic popliteal artery and very small amount of contrast was seen in the peroneal artery extending to the ankle suggesting proximal stenosis and extremely slow flow. 2. Left impression: abrupt cut off suggestive of acute thrombotic or embolic occlusion identified at the origin of the left common iliac arteries (iliac artery embolism, iliac artery occlusion) with propagation throughout the left lower extremity down to the popliteal artery. 3. On the delayed phase imaging, tiny wisp of contrast within the severely stenotic popliteal artery (peripheral artery stenosis) identified suggestive of very slow flow. The peroneal artery is also faintly patent on the delayed phase imaging with flow contrast extending to mid-calf level. Additional events were reported which occurred on an unspecified date in JUN-2021: peripheral arterial occlusive disease, peripheral artery occlusion, peripheral artery stenosis, peripheral artery thrombosis, poor peripheral circulation. The patient was hospitalized for 6 days. Due to severity of the ischemic limbs, he was offered bilateral above the knee amputations. He declined and would discharge from the hospital to hospice on 12-JUN-2021. Report stated "He is going to die." The patient had also visited Emergency Room (ER) for the events anal incontinence, angiogram peripheral abnormal, asthenia, back pain, Computerised Tomogram abdomen, Computerised Tomogram pelvis abnormal, diplegia, iliac artery embolism, iliac artery occlusion, peripheral arterial occlusive disease, peripheral artery occlusion, peripheral artery stenosis, peripheral artery thrombosis, poor peripheral circulation, and urinary incontinence. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The patient had not recovered from anal incontinence, angiogram peripheral abnormal, asthenia, back pain, Computerised Tomogram abdomen, Computerised Tomogram pelvis abnormal, diplegia, iliac artery embolism, iliac artery occlusion, peripheral arterial occlusive disease, peripheral artery occlusion, peripheral artery stenosis, peripheral artery thrombosis, poor peripheral circulation, and urinary incontinence. This report was serious (Hospitalization Caused / Prolonged, and Life Threatening).  Version created to amend previously reported information on 25/Jun/2021. Upon review, following information was amended: In event tab, for Emergency Room (ER) ticked as 'yes' for all the events and updated same in narrative too.; Sender's Comments: V1 The follow up version updates the following information: In event tab, for Emergency Room (ER) ticked as 'yes' for all the events and updated same in narrative too.The updated information does not change the causality of previously reported events.  This case, received from VAERS, concerns a 71 year-old male patient with diabetes, who presented with back pain, weakness, lower extremity paralysis and bowel/bladder incontinence, and was found to have critical lower extremity ischemia, 83 days after receiving the Janssen COVID-19 vaccine.  Angiography revealed occlusion of the left iliac and bilateral femoral and popliteal arteries. Events included iliac artery occlusion and embolism, and peripheral artery occlusion, stenosis and thrombosis.  No platelet counts were provided. The patient was offered amputations but declined; the events did not resolve and he was discharged to hospice.  The vessel stenosis is longstanding in nature and most likely related to his age and diabetes; the embolism/thrombosis may also be related to his chronic condition, and the latency between the events and the vaccine is long.  However, a relationship with Janssen Covid-19 vaccine cannot be ruled out and thus the relationship is considered indeterminate.