VII. 4. Known Risks and Contraindications

In the following conditions UltraBiome graft administration is prohibited. No clinical benefit outweighs these risks.

• Severe immunodeficiency. First 100 days after CAR-T therapy; first 100 days after allogeneic hematopoietic stem cell transplantation (HSCT); absolute neutrophil count (ANC) < 1.0 G/L; known primary immunodeficiency (e.g., CVID, SCID).
• Active malignancy under chemotherapy. During cytotoxic treatment the mucosal barrier is compromised, and the risk of translocation and bacteremia is critical.
• Severe acute abdominal condition. Acute diabetic gastroparesis, ileus, toxic megacolon, suspected perforation, or any active surgical abdomen.
• Pregnancy. No fetotoxicity safety data exist; actively avoid. A positive pregnancy test mandates immediate cessation of the UB program.
• Active IBD flare. Crohn’s disease with CDAI > 220; ulcerative colitis with Mayo score > 9. Re-evaluation is required in the remission phase.
• History of anaphylaxis to any UB graft component (capsule shell, excipient, donor-derived matrix).

The following conditions do not absolutely exclude UB use, but require individual clinical judgment and often multidisciplinary consultation.

• Breastfeeding. No data. Vertical bacterial transfer via subincubation is theoretically possible; only after physician consultation.
• Pediatric population (< 18 years). The UB program is not validated in children. Only with a special indication (e.g., severe ASD with microbiome-IBD overlap) and only under dedicated clinical supervision.
• Severe organ failure. NYHA III–IV heart failure; Child-Pugh C liver cirrhosis; eGFR < 30 mL/min/1.73 m² renal function.
• Active eating disorder. Anorexia nervosa, bulimia, BED in an acute stage — specialist care comes first; the UB program does not replace it.
• Active psychotic episode or uncontrolled major mood disorder. Avoid until stabilized.
• Chronic, intensive immunosuppression. In post-transplant or severe autoimmune protocols, only in coordination with the transplant team.

In June 2019, at Massachusetts General Hospital, two immunocompromised patients developed ESBL-producing E. coli bacteremia from a shared FMT donor graft; one patient died ^[49]. The FDA issued an immediate safety alert that reshaped the global donor screening standard.

Clinical consequences, also built into the UB protocol:

• Mandatory multidrug-resistant organism (MDRO) screening of every FMT donor: stool ESBL/CPE/VRE, plus rectal swab.
• The MicroBiome Bank donor protocol applies extended MDRO, viral, parasite, and metabolic screening; details are in the donor screening chapter of the Microbiota Guide.
• The treating clinician’s responsibility: any fever, sepsis of unknown origin, or suspected bacteremia after a UB graft → immediate blood culture + MDRO screen. The time window is critical: early detection determines outcome.

A MetSyn patient takes on average 4–7 medications. The table below summarizes the most common interactions and the corresponding clinical action.

• Pregnancy. No safety data. Actively avoid. If conception is planned, the UB protocol must be stopped before conception.
• Breastfeeding. No data. Individual judgment with physician consultation.
• Fertility. No data on effects on male or female fertility.
• In a woman of childbearing potential, effective contraception is recommended during the UB program.

In the population under 18 years, the UB program is not validated. In special situations (e.g., autism spectrum with severe overlapping GI symptoms), ongoing FMT IND studies in the USA provide a reference frame, but UB falls outside this. Due to the growth phase, the risk-benefit assessment is stricter, and any such case may only be initiated after a pediatric gastroenterology and pediatric infectious disease consultation.

Monitoring the first weeks after a UB graft is critical. A quick decision scheme for the clinician:

• Fever > 38 °C within the first 72 hours → blood culture + MDRO screen + empirical broad-spectrum antibiotic, per sepsis protocol.
• Severe GI event (vomiting > 3 episodes, bloody stool, severe abdominal pain, peritoneal signs) → acute hospitalization, emergency surgical consultation.
• Suspected anaphylaxis (urticaria + hypotension, dyspnea, laryngeal edema) → intramuscular epinephrine, emergency care.
• Chronic mild GI complaints (bloating, flatulence, transit changes) are common and expected in the first 2–4 weeks; monitor, but this alone is not a reason to stop the program.

This chapter is a quick reference for the clinician. The full donor screening protocol, UB batch traceability, and SOPs are available in the MicroBiome Bank professional documentation.