52 Fragmentation Hemolytic Anemia Flashcards
Two-thirds of HELLP patients are diagnosed antepartum, usually between_______ weeks
27 and 37 weeks
The remaining third are diagnosed in the postpartum period, from a few to 48 hours after delivery (occasionally as long as 6 days).
Risk factors for HELLP syndrome
- European ancestry
- Multiparity
- Maternal age (older than age 34 years), and
- A personal or familial history of the disorder
In a preeclamptic pregnancy, the second wave fails to penetrate adequately the spiral arteries of the uterus, perhaps as a result of reduced placental expression of ______
Syncytin
Functions as an antiangiogenic protein because it binds to vascular endothelial growth factor (VEGF) and placental growth factor (PGF) and prevents their interaction with endothelial cell receptors.
Soluble vascular endothelial growth factor receptor-1 (sVEGF receptor-1, or sVEGFR-1)
Ratio of sVEGFR-1 to PGF levels is increased.
Result is maternal glomerular endothelial cell and placental dysfunction
Another antiangiogenic molecule that is capable of binding to and inactivating the proangiogenic growth factors, TGF-β1 and TGF-β
Soluble form of endoglin (sEng)
The presence of elevated serum levels of both sFLT-1 (sVEGFR-1) and sEng may be associated with the progression of preeclampsia to HELLP.
Ninety percent of patients with HELLP syndrome present with
Malaise and right upper quadrant or epigastric pain
Fever is not typically seen.
Type of LDH
The ratio of ________(an isoenzyme found specifically in the liver) to total LDH is elevated in proportion to the severity of HELLP.
LDH-5
The high LDH seen in HELLP is most likely the result, principally, of ______________ rather than hemolysis
Liver damage
Liver enzymes usually return to normal within _______days postpartum.
3–5 days postpartum
Has been used in a classification system to predict maternal morbidity and mortality, the rapidity of postpartum recovery, the risk of disease recurrence, and perinatal outcome
Thrombocytopenia
BMA fonding: abundant megakaryocytes are found consistent with a consumptive thrombocytopenia causing reduction of the normal platelet lifespan of approximately 10 days to 3–5 days.
The platelet count nadir occurs 23–29 hours postpartum, with subsequent normalization within 6–days.
Mississippi triple-class system: based on platelet count
Class 1:
Class 2:
Class 3:
Class 1: less than 50 × 109/L ***highest incidence of perinatal morbidity and mortality
Class 2: between 50 and 100 × 109/L
Class 3:greater than 100 × 109/L
Class 1 HELLP syndrome have the highest incidence of perinatal morbidity and mortality and have the most protracted recovery periods postpartum.
TRUE OR FALSE
There is a indirect correlation between the extent of thrombocytopenia and measurements of liver function.
FALSE
There is a direct correlation between the extent of thrombocytopenia and measurements of liver function
But the same cannot be said for the severity of associated hepatic histopathologic changes.
TRUE OR FALSE
Unlike TTP, the thrombi found in organs involved in the HELLP syndrome contain increased amounts of fibrin and low levels of VWF.
TRUE
Unlike TTP, the thrombi found in organs involved in the HELLP syndrome contain increased amounts of fibrin and low levels of VWF.
- Prothrombin time (PT) and activated partial thromboplastin time (aPTT) are usually within normal limits
- von Willebrand factor (VWF) antigen levels increase in proportion to the severity of the disease, reflecting the extent of endothelial damage
- No unusually large VWF multimers are present in plasma,and ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin domains-13) levels are within a broad normal range
Seen in the last trimester or postpartum and presents with thrombocytopenia and right upper quadrant pain, but the levels of AST and ALT only rise to one to five times normal, and the PT and activated partial thromboplastin time (aPTT) are both prolonged
Acute fatty liver of pregnancy
Biopsy liver: fat in the cytoplasm of centrilobular hepatocytes; inflammation and patchy hepatocellular necrosis
Indications for delivery in HELLP
- Severe disease presentation
- Maternal DIC
- Fetal distress
- Gestational age greater than 32 weeks with evidence of lung maturity
TRUE OR FALSE
The use of dexamethasone has fallen out of favor after large randomized trials found that it did not reduce the duration of hospitalization, amount of blood products transfused, maternal complications, or time to normalization of laboratory abnormalities
TRUE
The use of dexamethasone has fallen out of favor after large randomized trials found that it did not reduce the duration of hospitalization, amount of blood products transfused, maternal complications, or time to normalization of laboratory abnormalities
TRUE OR FALSE
Plasma exchange cannot arrest or reverse HELLP syndrome when used antepartum but may minimize hemorrhage and morbidity when used peripartum.
TRUE
Plasma exchange cannot arrest or reverse HELLP syndrome when used antepartum but may minimize hemorrhage and morbidity when used peripartum.
Can also be tried postpartum in the 5% of patients who fail to improve within 72–96 hours of delivery.
Indications of liver transplantation in HELLP
Large hematomas or total hepatic necrosis
Hepatic hematoma is usually present in the ____________________
Anterior superior portion of the right lobe of the liver
Complain of right-sided shoulder pain and are found to be in shock with ascites or pleural effusions
Emergency surgery is required for hepatic artery embolization or ligation, hepatic lobectomy, or even liver transplantation in patients with total hepatic necrosis.
TRUE OR FALSE
One-third of all babies born to mothers with HELLP have thrombocytopenia
TRUE
One-third of all babies born to mothers with HELLP have thrombocytopenia
Intraventricular hemorrhage is seen very infrequently in thrombocytopenic infants
Fetal morbidity and mortality rates are each approximately 15%.
DISSEMINATED MALIGNANCY
80% of the tumors are mucinous adenocarcinomas of either the ____________________
MAHA is more likely to be associated with metastatic malignant disease than with localized cancers or benign tumors.
Stomach (55%)
Breast (13%)
Lung (10%).
The median age at diagnosis is 50 years, with a slight male predominance.
Two distinct mechanisms in Cancer-associated MAHA:
(a) DIC with intravascular occlusions (often partial) of small vessels by platelet-fibrin thrombi or
(b) Intravascular tumor emboli
TRUE OR FALSE Cancer-associated MAHA:
Although the reticulocyte count can be high, it is an unreliable measure of hemolysis because extensive replacement of the marrow by metastatic tumor may prevent the reticulocytosis expected with MAHA.
TRUE
Although the reticulocyte count can be high, it is an unreliable measure of hemolysis because extensive replacement of the marrow by metastatic tumor may prevent the reticulocytosis expected with MAHA.
The most common cause of anemia in malignancy is
Anemia of inflammation
Autoimmune hemolytic anemia secondary to malignancy is seen in:
Lymphoproliferative disease
Occasionally seen with carcinoma of the stomach, colon, breast, and cervix
Anemia was subsequently shown to be caused by erythrocyte shearing and fragmentation as the red cells traversed the turbulent flow through or around the prosthetic valve.
HEART VALVE HEMOLYSIS
Factors can increase the chance of valvular hemolysis
- Presence of central or paravalvular regurgitation
- Placement of small valve prostheses with resultant high transvalvular pressure gradients
- Regurgitation because of bioprosthetic valve failure, seen especially when the valve is more than 10–15 years old
A transvalvular pressure gradient of more than 50 torr can generate shearing forces exceeding 4000 dynes/cm2, more than the ___________ dynes/cm2 usually needed to cause red cell fragmentation.
3000 dynes/cm2
The presenting complaint is passage of dark urine immediately after physical exertion in the upright position, occasionally accompanied by nausea, abdominal cramps, aching in the back or legs, a “stitch in the side,” or a burning feeling in the soles of the feet
MARCH HEMOGLOBINURIA
Anemia is uncommon
Morphologic evidence of red cell damage is not seen
Renal damage is also not commonly seen
A syndrome that usually develops in early childhood and is characterized by thrombocytopenia, MAHA, consumptive coagulopathy, and hypofibrinogenemia caused by an enlarging kaposiform hemangioendothelioma or tufted angioma.
Kasabach-Merritt phenomenon
