Rh- mother w/ Rh- child and direct coombs+? Is it possible?

[travleur]

hi,

i am currently practicing cgfns questions (exam coming nov 11th!!). i think it is a mistake from the cgfns book (which, unfortunately, is quiet common on the cgfns practice guide) but i wanted to make sure i was not missing some information.

here is the question:

the nurse preceptor should intervene if the caring for an rh-neg mother tells the mother that she would need to receive rho (d) immune globulin (rhogam) within 72 hours of:

a. delivery of an rh negative, coombs positive infant

b. abortion or miscariage

c. delivery of an intrauterine fetal demise

d. delivery of an rh positive infant

answer:

a. the nurse preceptor should intervene if the nurse caring for the rh-neg mother who delivers an rh-neg, coombs positive infant tells the mother that she needs rhogam within 72 hours. the nurse preceptor needs to explain to the nurse that rhogam is not needed because the infant's coombs is positive. if the infant's cord blood direct coombs test was negative, then the nurse would give rhogam because this indicates that an ag-antibody response has not already occurred.

obviously by process of elimination you can come up with the right answer. i just wanted to make sure that it is a mistake and that they meant a rh+ baby. there is no way a rh- mum with a rh- baby give a positive coombs test right? or am i forgetting a possible scenario here?

it is very annoying to have so many mistakes in a study guide. there is even several examples where 2 of the exact same question have different answers supported by different explanation (especially in psychiatry) then you don't really know what to think!

anyway, thanks for any help.

[DuluthMike]

A is correct. What did your guide say the correct answer is? There is no need to administer Rhogam is both mother and child are rh-.

[lindarn]

My blood type is O+. My husband is A-. My daughter is A+. When she was born, she jaundiced within hours after she was born. She was under the bili lights before the night shift went off shift, and she was born at 11:55 PM.

She had ABO incombatibility- like being given the wrong blood tranfusion. Her Coombs test, off of her cord blood, was +.

Lindarn, RN, BSN, CCRN

[travleur]

A is correct. What did your guide say the correct answer is? There is no need to administer Rhogam is both mother and child are rh-.

Sorry, I should have mention it more clearly, yes the correct answer is A. But my question is: is it possible to have a coombs + if the mother and the infant are Rh-?

[travleur]

My blood type is O+. My husband is A-. My daughter is A+. When she was born, she jaundiced within hours after she was born. She was under the bili lights before the night shift went off shift, and she was born at 11:55 PM.

She had ABO incombatibility- like being given the wrong blood tranfusion. Her Coombs test, off of her cord blood, was +.

Lindarn, RN, BSN, CCRN

That's a completely diffrent scenario. Your case was for ABO incompatibility, RhoGAm is for Rh incompatibility.

[makes needs known]

I am B- and my husband is O+, and during all 3 pregnancies I had the shot just in case I was carrying a Rh+ child. After they were born and each baby was B-, same as my blood type, I did not need the shot.

[iteachob, MSN, RN]

Sorry, I should have mention it more clearly, yes the correct answer is A. But my question is: is it possible to have a coombs + if the mother and the infant are Rh-?

I understand what you're saying, if mom and baby are both negative (without Rh factor), then where the heck is the sensitization coming from (??), and I agree with you.......this is a head scratcher! I'm going to try and find out the answer. And you're right...it may be a book error.

[iteachob, MSN, RN]

Hmmm, I've been looking for a few minutes and found this:..."false positive" is a possibility. Of course, that would require a bit of "reading into" the answer, and we all know that's a no-no. More likely a book error.