A 79-year-old female patient presented at the hospital with
osteoarthritis. Examination of the patient revealed hemoglobin
level of 10.8 g/dL, RBC count of 3.45x106
/µL, WBC count of
10.1x103/µL, and platelet count of 122x103
/µL. Plasma levels of
blood urea nitrogen, creatinine, sodium, potassium, and alanine
aminotransferase were all within the normal ranges, while
aspartate aminotransferase was slightly higher than normal. A
blood sample obtained from the patient was submitted to our
division for blood typing and cross-matching, with a request
to receive 2 units of packed red blood cells. ABO typing was
performed using standard serological techniques after an
immediate spin. Testing the patient’s red blood cells revealed no
detectable ABO antigens upon forward/cell grouping (group O
blood type). On the other hand, reverse/serum grouping showed
the presence of A antibodies in the serum (group B blood type).
To resolve the discrepancy between cell and serum grouping we
performed an agglutination examination of anti-H serum; the
red blood cells from the sample did not exhibit an agglutination
reaction. Additionally, secretor status was determined in order
to assess the presence of soluble blood group substances.
Our results showed the presence of B and H antigens in the
saliva. Based on these results, the patient in the present case
was diagnosed as having a para-Bombay B phenotype (Table 1,
Figure 1).
