Rh deficiency syndrome
MONDO:0019107The Rh deficiency syndrome, also known as Rh-null syndrome, is a blood disorder where people have red blood cells (RBCs) lacking all Rh antigens. The Rh antigens maintain the integrity of the RBC membrane and therefore, RBCs which lack Rh antigens have an abnormal shape. There are two types of Rh deficiency syndrome: The regulator type is associated with many different changes (mutations) in the RHAG gene. The amorph type is caused by inactive copies of a gene (silent alleles) at the RH locus. As a result, the RBCs do not express any of the Rh antigens. The absence of the Rh complex alters the RBC shape, increases its tendency to break down (osmotic fragility), and shortens its lifespan, resulting in a hemolytic anemia that is usually mild. These patients are at risk of having adverse transfusion reactions because they may produce antibodies against several of the Rh antigens and can only receive blood from people who have the same condition. Rh deficiency syndrome is inherited in an autosomal recessive manner. Management is individualized according to the severity of hemolytic anemia.
Also known as: Rh deficiency syndrome, Rh-null syndrome, anemia, hemolytic, Rh-null, regulator type, RH-null, regulator type, RHN, RHNR, Rh-Mod, Rh-null disease
7 clinical trials for this condition and its sub-types.
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New anemia drug enters early human testing
Symptom relief Recruiting nowThis early-stage study tests a new drug called APG-5918 in healthy volunteers and people with anemia (low red blood cells). The main goal is to check safety and how the body handles the drug, while also seeing if it can raise hemoglobin levels. About 105 participants will take pa…
Phase: PHASE1 • Sponsor: Ascentage Pharma Group Inc. • Aim: Symptom relief
Last updated Jun 27, 2026 12:08 UTC
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Hospital tests if its own anemia rules actually get followed
Knowledge-focused Recruiting nowThis study looks at whether doctors at Siriraj Hospital follow a new guideline for treating anemia in patients before major surgery. Anemia is common in surgical patients and can lead to more blood transfusions and worse outcomes. The researchers will track 93 anemic patients to …
Sponsor: Siriraj Hospital • Aim: Knowledge-focused
Last updated Jun 27, 2026 09:11 UTC
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Anemia type may predict surgery danger
Knowledge-focused Recruiting nowThis study is observing 1000 adults having moderate- to high-risk surgery to see if the type and severity of anemia they have before surgery affects their risk of complications like heart injury, kidney injury, or stroke. Researchers will compare patients with iron-deficiency ane…
Sponsor: Peking Union Medical College Hospital • Aim: Knowledge-focused
Last updated Jun 27, 2026 08:00 UTC