# Extremely Rare Blood Types Resulting in Non-compatibility in the Perioperative Surgical Setting: A Case Report

## TL;DR

A rare blood type, Junior negative, caused challenges in blood compatibility during a cesarean section, requiring special hematologic and surgical planning.

## Contribution

This case report highlights the clinical challenges and management strategies for patients with the extremely rare Junior negative blood type.

## Key findings

- The patient had a rare Junior negative blood type with anti-Junior antibodies, incompatible with over 99% of blood products.
- Specialized contingency and transfusion planning was required to manage the patient's perioperative care safely.
- The case emphasizes the importance of identifying rare blood types early to prevent maternal hemorrhage risks.

## Abstract

Peripartum patients with rare blood groups (such as the Junior negative, Kell, Kidd, and Lewis antigen blood groups) can be extremely difficult to care for, even when appropriately typed and screened, crossed, and antibody tested for blood type compatibility. Here, we present a case report of a 37-year-old gravida 2 para 1 with one prior full-term singleton birth presenting for a scheduled cesarean section who was identified through routine preoperative testing to have an extremely rare blood type: Junior negative with the presence of anti-Junior antibodies. The Junior negative blood type is incompatible with over 99% of all blood products as the Junior antigen is very high frequency in almost all populations and present universally on red blood cells irrespective of ABO and rhesus (Rh) blood type. The hematologic and perioperative considerations of the patient will be discussed in this case report to include pathophysiology of the Junior-encoding gene, patient maternal hemorrhage, contingency planning, blood transfusion planning, intraoperative management, and patient outcome.