15: Transplant Flashcards
When is engraftment first evident in a transplant patient? How long does that typically take?
When new white blood cells, red blood cells and platelets being to appear in the patient’s blood. Usually not until week 2-3 post infusion.
What are the 3 types of HCT? Describe them each.
Autologous HCT - uses patient’s own stem cells, collected before the conditioning regimen. Mainly used for NHL, HL, MM
Syngeneic HCT - using identical twin stem cells – rare for obvious reasons
Allogeneic HCT - used stem cells from a donor. Mainly used for acute/chronic leukemias, NHL, and marrow diseases like Aplastic Anemia. This can have several types.
What are the different types of Allogeneic HCT?
Matched related Donor
Matched unrelated Donor (MUD)
mismatched unrelated Donor
half-matched related Donor (Haploidentical or Haplo)
Umbilical cord blood
What are the different conditioning regimens for transplant?
It requires either cytotoxic chemo, TBI (total body irradiation) or both
High-Dose or myeloalative regimens – combo of chemo to ablate bone marrow that requires stem cell infusion in order to rebuild the bone marrow
Nonmyeloablative regimens – chemo that cause minimal cytopenias, so patient doesn’t need stem cell infusion
Reduced intensity conditioning (RIC) — less intense chemo or TBI (or both) that causes prolonged cytopenia, resulting in need for stem cell infusions
What mechanism does the RIC or nonmyeloablative regimens (aka lower dosage) for conditioning rely on for full disease eradication? When/why would these be used?
graft-versus-tumor (GVT) effect – response in which the infused graft stem cells attack and kill remaining cancer cells that weren’t killed by the conditioning.
Often used in older patients, have been heavily pretreated, or have comorbidities and unable to tolerate high-dose
What’s the typical timeline for neutrophil engraftment by transplant type?
Auto — 10-12 days
Allo —
MRD/MUD with peripheral blood and Haplo — 14-16 days
MRD/MUD with bone marrow — 19-21 days
Umbilical cord blood — 21 days
What type of diet should patients be on post transplant?
Food Safety Diet – reduce risk of foodborne illness
Really restrictive diets are not supported by evidence. Foodborne illness is rare in first year post transplant if patients follow guidelines:
AVOID
raw/undercooked meat (including game), fish, shellfish, poultry, eggs, sausage and bacon
avoid raw tofu, unless pasteurized
lunch meats unless heated until steaming
unpasteurized dairy
blue-veined cheeses, uncooked soft cheeses, mexican-style soft cheeses, cheese containing chili peppers and uncooked vegetables
refrigerated smoked seafood and pickled fish
fresh salad dressings that contain raw eggs or above cheeses
unwashed raw or frozen fruits/veg and those with visible mold
all raw vegetable sprouts
unpasteurized fruit/vegetable juice
well water unless boiled for 15-20 minutes and consumed within 48 hours
How long are HSCT patients on the required diet?
Food Safety Diet
auto – about 90 days post transplant
allo – until off immunosuppressive therapy, which varies by health care facility and type of match. Usually at least 3-6 months, could be longer
How does being underweight or overweight impact survival?
underweight — increased risk of relapse, poor overall survival
overweight — increased risk for nonrelapse mortality. Also at increased risk for GVHD.
What are the typical oral/GI complications of transplant?
These are frequent. Conditioning regimens side effects typically start to diminish as engraftment begins.
These are commonly taste loss, nausea, early satiety and mucositis.
What method is used to reduce the risk of mucositis in high-dose conditioning regimens?
Cryotherapy – the placement of ice chips in the mouth during infusion-with melphalan helps reduce mucositis by decreasing blood flow and exposure to chemo. This is a great tool to use since up to 80% of patients develop this.
Describe SOS or Sinusoidal Obstructive Syndrome
The effect of chemo causes sinusoidal endothelial and hepatocyte damage that triggers a cascade of events leading to narrowing and occlusion of hepatic venules, fibrosis, and hepatocyte necrosis. This causes decreased hepatic outflow, portal HTN, ascites and hepatomegaly, and cause cause multiorgan failure and death.
Usually occurs within first few weeks of transplant and incidence varies widely to 0-60% based on transplant type, diagnostic criteria used and population risk factors. Has a high mortality rate exceeding 80%.
Medical management using diuresis, sodium restriction, renal replacement therapy (HD or CRRT), pain management and use of defibrotide.
What two main lab issues can occur with transplant and why?
Hyperglycemia – usually by meds, typically prednisone, or by use of TPN. Usually during the neutropenic phase for HCT, causing delays in neutrophil recovery, function, and increased risk for infection/prolong engraftment time and risk for acute GVHD.
Renal impairment – could be chemo, TBI, nephrotoxic meds like antibiotics, SOS, intravascular volume depletion and sepsis. Nutrition should work to max nutrition support within fluid allowance, correcting electrolyte imbalance and maintain sufficient intravascular volume.
What is a major source of morbidity and mortality for patients receiving HCT?
Infection – bloodstream infections, pneumonia and GI infections like C Diff are the most common. TPN/PN could be another source concern.
What do about half of all patients develop within the first 100 days? What different forms can it take?
Clinically Significant Cytomegalovirus (CSV)
CMV enteritis - nonspecific GI that can cause ulcerations anywhere along the GI tract. Diagnosed via biopsy to rule out other causes.
CMV gastritis - often causes severe epigastric pain
CMV esophagitis - present at odynophagia and dysphagia
CMV colitis - may cause diarrhea, abd pain, anorexia, and fever
