HY lecture notes:
Uteroplacental insufficiency = placental under-perfusion –> caused by things like SLE (lupus anticoagulant), anti-phospholipid syndrome, smoking, and cocaine use. Leads to recurrent miscarriage in the setting of SLE (lupus anticoagulant) and anti-phospholipid syndrome.
Uteroplacental insufficiency causes intrauterine growth restriction (IUGR), which is best measured by abdominal circumference. Sounds weird, because you’d think another parameter like head circumference, biparietal distance, femur length, etc., would be an ideal reflection, but the USMLE wants abdominal circumference.
Now above we talked about some causes of uteroplacental insufficiency. But the USMLE also wants you to know that pre-eclampsia/eclampsia are due to uteroplacental insufficiency. That is, if perfusion to the placenta is insufficient, the cardiovascular system will attempt to augment the perfusion by increasing blood pressure.
Mastitis is the majority of the time a red, cracked, fissured nipple in a breastfeeding woman. Organism is S. aureus. Answer is continue breastfeeding through the affected breast. Give her oral dicloxacillin or cephalexin (safe during breastfeeding).
However the 2CK wants you to know that mastitis can also present as a non–fluctuant mass not affecting the nipple. There’s a Q on one of the obgyn forms where they say there’s an upper-outer quadrant, red, warm, tender, non-fluctuant mass –> Dx? –> mastitis, not abscess. This is where students say, “Wtf? I thought mastitis is a red, cracked, fissured nipple in a breastfeeding woman.” Yeah, you’re right, but it can also present as a non-fluctuant mass.
Red, warm, tender mass:
If they say non-fluctuant –> mastitis; Tx = if breastfeeding, continue doing so through the affected breast. Give oral dicloxacillin or cephalexin.
If they say fluctuant –> abscess –> must drain. Always drain abscesses / pus collections on the USMLE. Even if Abx are also listed and your thought is, “Well yeah I’d drain, but wouldn’t we still at least start the patient on Abx first?” No. On the USMLE, they want drain first. Always.
Fat necrosis of breast –> non-enzymatic (whereas enzymatic fat necrosis is pancreatitis). Caused by trauma, tight-fitting sports bras, etc. Can calcify.
Fibroadenoma –> most common tumor of breast overall; usually seen in younger women; rubbery, mobile, painless, singular mass. Although not sinister, must remove because it’s still neoplasia.
For simple cysts (i.e., no solid components seen on ultrasound or mammography), small ones can be observed; otherwise FNA (fine-needle aspiration) is the intervention if you are forced to choose. If a patient was recently started on HRT (hormone-replacement therapy), new simple cysts must be drained (i.e., never observed); if there is any component of the cyst remaining after drainage, do biopsy.
HRT is only ever indicated for severe vasomotor symptoms in women accompanying menopause; it is NOT given to prevent bone loss, etc. It increases the risk of thromboembolic phenomenon (MI, stroke) and breast cancer.
Fibrocystic change –> usually bilateral breast tenderness seen in younger women that waxes and wanes with menstrual cycle –> blue dome cysts, sclerosing adenosis, apocrine metoplasia; however, there’s a Q on one of the newer obgyn forms where a woman has a unilateral, painless mass that drains a serous, brown fluid on FNA, and the answer is fibrocystic change.
In other words, same way you’ve learned above about a less common way that mastitis can present, you now know of a less common way that fibrocystic change presents. But these variants are both clearly assessed.
Unilateral bloody nipple discharge = intraductal papilloma until proven otherwise; however if they do biopsy and histo shows “stellate morphology,” answer is invasive ductal, not intraductal papilloma.
Paget disease of breast –> eczematoid nipple with underlying ductal carcinoma in-situ (DCIS). Histo of Paget shows Paget cells (large, clear cells).
Lobular carcinoma –> bilateral breast cancer –> histo shows linear rows of cells (“Indian file”) –> lack of E-cadherin allows cells to avoid clumping (in ductal, the cells are not linear because they are E-cadherin-positive).
Mammary ductal ectasia –> presents as inverted nipple.
