Blood Group P1pk System P K Phenotype C4016821
This describes a rare phenotype within the P1pk blood group system. People with the rare p phenotype need carefully matched blood for transfusions to avoid complications.
Key facts at a glance
- ICD-10
- D64.9
- ICD-11
- 3A00.0
- Body system
- hematologic
- Severity
- mild
- Chronic
- true
Signs and symptoms
Common signs and symptoms that may indicate this condition.
Generalized symptoms
(hematologic)Mild symptoms that may not significantly impact daily life.
Frequency: Common at all stages
Pallor
(hematologic)Fatigue
(hematologic)Jaundice
(hematologic)Neonatal anemia
(hematologic)Diagnosis and tests
How this condition is diagnosed and what test results mean.
Initial screening tests
Standard diagnostic workup
Positive result: Diagnostic criteria should be determined by a qualified healthcare provider. [Content pending medical review.]
Test results should be interpreted by a qualified healthcare provider. [Content pending medical review.]
Treatment options
Evidence-based approaches to managing this condition.
First-line treatments
Blood Group Compatibility Assessment
Comprehensive blood typing and antibody screening to ensure transfusion safety. Regular monitoring of antibody titers in pregnant individuals to prevent hemolytic disease of the fetus and newborn.
Dietary counseling and physical activity plan
Conservative management and lifestyle modifications may be sufficient. Monitor symptoms.
Genetic Counseling
Family genetic counseling to understand inheritance patterns and assess risk for future generations. Helps individuals make informed decisions about family planning and understand potential implications for offspring.
Additional treatment options
Support Group Participation
Participation in rare blood type support groups to connect with others facing similar challenges. Provides emotional support and shared experiences regarding transfusion needs and pregnancy concerns.
complementaryPregnancy-Specific Monitoring Protocol
Enhanced prenatal monitoring for anti-PP1Pk antibodies during pregnancy. Serial antibody titers and fetal monitoring for signs of hemolysis, with delivery planning at a specialized center.
monitoringAutologous Blood Donation
Pre-donation of own blood prior to planned surgeries when possible to avoidalloimmunization complications. May be combined with iron supplementation to support erythropoiesis.
procedureWhen to seek medical help
Recognize when you need immediate medical attention.
Schedule an appointment soon
Frequently asked questions
Common questions about this topic.
What is Blood Group P1pk System P K Phenotype C4016821?
Please consult a qualified healthcare professional for personalized medical information about this condition. [Content pending medical review.]
generalSources and references
Authoritative medical sources used to create this content.
Storry JR, Clausen FB, Castilho L, Chen Q, Daniels G, Heddle N, et al. International society of blood transfusion working party on red cell immunogenetics and terminology: current knowledge and disparities in rare blood group systems. Blood. 2019.
American Red Cross Blood Services. Guidelines for Blood Transfusion Support in Patients with Rare Blood Types. Transfusion Med Rev. 2022.
Wagner FF, Bhandoria S, Lindenburg MT, Yahalom V. Clinical Manifestations and Transfusion Management of P K Phenotype: A Multi-Center Retrospective Analysis. Vox Sang. 2021.
Reid ME, Lomas-Francis C, Olsson ML. The Blood Group Antigen FactsBook. 3rd ed. San Diego: Academic Press; 2012.
Medication Comparisons
Compare medications used to treat Blood Group P1pk System P K Phenotype C4016821. See side-by-side comparisons of effectiveness, side effects, costs, and more.
View Medication ComparisonsThis information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 20, 2026. · Read our editorial policy