massive infection that involved all internal organs/major massive infection, and the patient was on antibiotics; excruciating pain/abdominal pain/lower right quadrant, it was in left too and general/whole stomach was in excruciating pain; vomiting/couldn't keep anything down; chills; diarrhea; hasn't been eating or slept much; hasn't been eating or slept much; weighs a lot less than she did before; appendicitis; ruptured appendix; inflamed colon/colon inflammation; This is a spontaneous report from a contactable consumer (patient's sister). An elderly female patient (reporter's sister) received bnt162b2 (PFIZER-BIONTECH COVID-19 VACCINE, solution for injection), dose 1 via an unspecified route of administration on 09Mar2021 (mid afternoon) (batch/lot number not reported) as single dose for covid-19 immunization at a pharmacy/drug store and not administered at military facility. The reporter informed that the reason for no lot number was that the patient and her live in different states and the reporter did not have the card. The patient's medical history was none. The reporter informed that a patient's family member in decades has had an issue with appendix. The patient's concomitant medications were not reported. The patient has no history of all previous immunization with the Pfizer vaccine considered as suspect and no additional vaccines administered on same date of the Pfizer suspect (vaccine). The patient has no prior vaccinations (within 4 weeks). On 13Mar2021, the patient experienced appendicitis. The reporter informed that the patient experienced a ruptured appendix and inflamed colon (colon inflammation) on 13Mar2021 (onset also reported 17Mar2021 for colon inflammation, pending clarification) which was 4 days after getting the first dose of the Pfizer COVID-19 vaccine. The reporter informed that the patient had an emergency appendix rupture four days after having her shot. The patient had zero pain beforehand. The reporter added that there was a massive infection that involved all internal organs (unspecified date) and the doctors were bewildered by the event because the patient did not have any prior pain. The reporter informed that the doctors have said that the patient had massive infection in and around all organs in that area. The reporter informed that they can't understand how it would happen so fast, they'd ask her if she had any pain in advance. The reporter stated "no, she was fine before and after the shot but then four days later (13Mar2021), all of a sudden the patient had excruciating pain". The reporter informed that they say it was a very complicated case and they can't see how it went acute so fast.  The reporter informed that the patient wasn't in a position to absorb the information, so they didn't go into it, but they were bewildered as to how advanced it was, so they continued to ask about history. The patient was asked if she was sure that she had no pain before that. The reporter informed that "they" were also concerned about the colon. The reporter informed that the gastroenterologists and other hospital critical care people were taking care of her. The reporter clarified that the patient was having abdominal pain but it was not initially in the lower right quadrant, it was in left too and general, never specific to her where she would feel pain on right. The pain in general was all over up to diaphragm. The reporter informed that on 13Mar2021, the patient's whole stomach was in excruciating pain, she had repeated vomiting, no fever, some chills which they associated with the vomiting and pain. The reporter informed that the patient had diarrhea as well. The reporter clarified that the first thing was pain and vomiting at same time, diarrhea developed later that evening. On 13Mar2021, the patient hasn't been eating or slept much. The reporter clarified that every time she tried to, like when she would have short reprieved of vomiting, and have a little broth or liquid just enough to see, she couldn't keep anything down. The reporter informed that the patient weighs a lot less than she did before. The reporter informed that the events required emergency room visit on 15Mar2021. The patient was in the ER for 36 hours because the hospital didn't have beds available, they were over run. The patient was hospitalized due to the events on 15Mar2021 discharged on 18Mar2021. The reporter informed that the reason they wanted her out of the hospital was because of the high risk of catching something that "you all were trying very hard to prevent". The reporter informed that the events did not required physician office visit. The patient didn't need for doctor before onset. Therapeutic measures were taken as a result of the events. The reporter informed that after a severe major massive infection, and the patient was on antibiotics. The reporter informed that they have been pumping the patient with antibiotics for several days and it was helping (assuming based on that that the patient has improved). The reporter informed that they have been able to force the numbers back to closer where they would like to be. The reporter informed that they say her colon, even though numbers coming back which means infection receding, the colon was inflamed. The reporter informed "they" can't do the operation until 6 weeks after the infection. The outcome of the events appendicitis, ruptured appendix, inflamed colon/colon inflammation, excruciating pain/abdominal pain/lower right quadrant, it was in left too and general/whole stomach was in excruciating pain, pain in general was all over up to diaphragm was recovering, hasn't been eating or slept much was not recovered, while unknown for the rest of the events. The reporter wanted to know, assuming the infection and inflammation has gone better, whether the patient take the second dose of the vaccine as scheduled. The reporter wanted to know if the immune system will be too fired up when getting the second dose of the vaccine and if should the patient even get the second dose of the vaccine. The reporter also wanted to know what the recommendation was about getting the second shot at this time. The reporter informed that the 3 weeks or 21 days will come while she was somewhat compromised. The reporter wanted to know if there was a link between ruptured appendix or inflamed colon after getting the Pfizer COVID-19 vaccine. The reporter informed that nobody has said there was any connection. The reporter informed that it seemed that there was a possibility that it was connected to the vaccine because in an otherwise healthy person, it was hard to explain. The reporter hoped to find out if there were other situations like this so she could tell the patient that they [Pfizer] determined that and she [the patient] needs to mention to the doctors. The reporter didn't mean to tell anyone what they should be doing at this point, but the reporter wanted to be able to give a position.   Follow-up activities are possible, information on the batch number has been requested.