Medical Terms

Two summers ago I took a medical terminology class which has helped me understand some of the terms I've heard. So here are some explanations of why I hear these words too much--uh, I mean, so much.


absolute neutrophil count (ANC) - the number of neutrophils in one microliter of blood; a low ANC means one runs a high risk of infection; when I get a fever and my ANC is lower than 1000 (which is almost always the case if I have a fever in the first place) I automatically get antibiotics

anemia - "not enough" red blood cells or hemoglobin (RBC < 3.80 x 106 or HGB < 12.0 g/dL for women); many things can cause anemia and chemotherapy is definitely one of them; symptoms can include fatigue, tachychardia (fast heartbeat), paleness, dizziness, and shortness of breath; treatment for mild anemia can include weekly subcutaneous injections of Epogen, for more severe anemia treatment can include red cell blood transfusions (when my HGB < 7.0)

CBC + Diff (complete blood count and differential) - a CBC measures the total number of the different types of blood cells: erythrocytes (red blood cells - "RBC"), leukocytes (white blood cells - "WBC"), and platelets found in one microliter of blood; the differential (Diff) includes a breakdown by percent and total number of the different types of leukocytes; at times my life revolves around my blood counts

Important CBC Ranges
White Blood Cells Normal Range Critical Range
WBC (total white blood cell count) 3.9-10.8 x 103/µL
ANC (absolute neutrophil count) 1.8-7.7 x 103/µL < 1,000

Red Blood Cells Normal Range (Female) Transfusion Needed
RBC (red blood cell count) 3.80-5.20 x 106/µL
HGB (hemoglobin) 12.0-16.0 g/dL < 7.0 or when symptoms of anemia are present
HCT (hematocrit) 35.0-47.0%

Platelets Normal Range Transfusion Needed
PLT (platelets) 140-440 x 103/µL < 10,000 with no fever
< 15,000 with fever over 100.5° F

CHOP - the combination of four drugs Cytoxan, Adriamycin, Vincristine, and Prednisone used in the treatment of non-Hodgkins lymphoma; go to my Drugs page for more info on these drugs

CT scan - computed tomography scan

CMV (cytomegalovirus) - a common virus found in 4 out of 5 people over the age of 35; in people with healthy immune systems it is harmless, but in immunosuppressed people it can cause cytomegalic inclusion disease which can lead to pneumonia; it can be transmitted through blood transfusions (or from a mother to her fetus)

erythrocyte, red blood cell (RBC) - the primary function of red blood cells is to carry oxygen, each cell has over 200 million molecules of oxygen-carrying hemoglobin; RBCs originate from stem cells in the bone marrow and live for about 120 days

gauge - unit for the diameter of a needle; the higher the number, the thinner the needle; IM injections (like flu shots and tetnas boosters) typically use 1" 22-gauge needles, SC injections (like my Neupogen shots) use 5/8" 26-gauge needles, blood donation uses 16-gauge or 18-gauge needles (they need to use big needles so that the blood cells aren't harmed going through a small opening)

hemoglobin (HGB) - a molecule found in red blood cells that carries oxygen from the lungs to the tissue by forming a compound called oxyhemoglobin (1g HGB + 1.36cc O2 -> you go work out the moles, I've had enough chemistry for now); consists of heme, an iron-containing pigment, and globin, a simple protein

hematocrit (HCT) - the percentage volume of erythrocytes in the blood

HyperC-VAD - a chemotherapy regimen including Cytoxan, Adriamycin, Vincristine, Dexamethasone, and three other drugs which I am not getting

ICE - a three drug chemotherapy salvage regimen including Ifosfamide, Carboplatinum, and Etopicide; Mesna is also given to protect the bladder and kidneys

intussuception - Taber's Cyclopedic Medical Dictionary gives a much better description than any I could come up with:

The slipping of one part of an intestine into another part just below it; becoming ensheathed. It is noted chiefly in children and usually occurs in the ileocecal region. Prognosis is good if surgery is performed immediately; but mortality is high if this condition is left untreated more than 24 hours. (Thomas 1997)

Geez, I didn't know that last part and I'm not sure I wanted to. The reason this happened to me was that I had a tumor in the last part of my small intestines which was grabbed by the muscular contractions of the intestine (peristalsis) and pulled into my large intestine as if it were a piece of food. Only one problem, when the tumor was pulled through it was still attached to my small intestine so my intestines were pulled "inside-out." As you might imagine, this caused a lot of pain and lasted for a long time. I'm quite certain it was in the range of several days or even weeks--in any case, I'm sure it was "left untreated for more than 24 hours."

leukocyte, white blood cell (WBC) - there are several types of WBCs, the granulocytes: basophils, eosinophils, and neutrophils and the agranulocytes: monocytes and lymphocytes; with chemo I am mostly concerned with my total number of WBCs, the neutrophils, and to a lesser extent, the monocytes (which, I've been told, can tell me when my counts are on the verge of going up); the WBC's and particularly neutrophil's primary function is to fight infection (among other things); the granulocytes originate from stem cells in the bone marrow, agranulocytes originate from the spleen, lymph nodes, and thymus; I don't know exactly how long WBCs live, but it is a much shorter time than RBCs--it's more than a few days and less than a few weeks

nadir - the period after chemo during which blood counts (particularly the WBC) are the lowest--generally 10-14 days after chemo; I used to think this term was spelled like (Ralph) Nader because it sounds the same

neutropenia - a low neutrophil count (i.e. an absolute neutrophil count below 1.0 x 103); a short period of neutropenia is a common side effect of most chemotherapy, it tends to occur about 10 days after chemotherapy and lasts several days (these days are known as the nadir); the nadir can be shortened with daily subcutaneous injections of Neupogen (see my Drugs page for more info on Neupogen) starting 24 hours after the last chemotherapy drug and continuing for at least 7 days or until the WBC comes up; antibiotic prophylaxis is sometimes necessary to prevent infections during periods of neutropenia; many precautions must be taken when I'm neutropenic: I can't be near fresh flowers or plants, I have to eat a low-microbial diet meaning no fresh uncooked foods or foods with active cultures like cheese or yogurt, I also have to wash my hands so often that they get all dry even when I use lotion; there are several other terms you will hear in conjunction with neutropenia like "immunosuppressed" and "immunocompromised" all of which basically suggest that a person has a weak immune system and little defense against infection

neutropenic fever - a combination I'd rather avoid because it means a trip to the clinic or the ER: fever > 100.5° F + ANC < 1000 = IV antibiotics every day until my counts come up; luckily antibiotic prophylaxis usually helps me avoid this unpleasant situation

neutrophil - a type of white blood cell that fights infection; neutrophils usually make up about 55-70% of total WBCs

PET (positron emission tomography) scan - this type of scan is good for differentiating between active tumor and necrosed (dead) tumor both of which would look the same on a CT scan; radioactive labeled glucose is infused into my bloodstream and gobbled up by my cells which are starving for glucose because I haven't eaten for 6 hours prior to the scan, then I lie in the center of a donut-shaped machine for 8 minutes per 15cm of my body which comes out to a total of about 45 minutes, the machine maps where in my body the radioactive glucose has gone in other words which are the most active cells, the result is a series of pictures (that look similar to CT scan results) showing dark areas where there are active cells (not just tumor cells) in my body

platelet (PLT) - the type of blood cell that makes blood clot; there is an increased risk of bleeding with platelet counts lower than 20,000 (per microliter of blood); platelet transfusions are necessary when the count drops lower than 10,000 or 15,000 with a fever because a fever decreases the body's ability to control bleeding

port - a catheter that is kept in a vein for easier IV access; There are several types of ports. The kind I have has a small round "injection site" under the skin in my chest. This is attached to a thin tube (a.k.a. catheter) that runs through a vein all the way to my heart where there is a high volume of blood flow. This kind of port is entirely under the skin--there are no tubes sticking out which could cause infection. The port is accessed by poking a special needle which is attached to an IV line into the injection site. The port reduces the risk that my veins will be damaged by the toxic chemo drugs or repeated poking. Also, blood can be drawn from the port for labwork. I've been told my port draws blood very well which is a good thing because it means I don't have to get stuck in the arm too much.

prophylaxis - prevention
antibiotic prophylaxis - sometimes I take oral antibiotics during my nadir to prevent neutropenic fever

saline - salt water solution (0.9% sodium chloride in distilled water); used for many things one of which is to hydrate a person intravenously (most people know what saline is, but I am always surprised how often I assume people know something when they don't which is why I'm explaining it anyway)

salvage treatment - the term used for the treatment of relapsed cancer--not exactly the word I would choose to mean this if I were the one making up the medical terminology, but whatever


My Shorthand Terms

"my counts" - When I refer to "my counts" I am refering to my complete blood count (CBC) but more specifically the white blood cell (WBC) part of the CBC. If I mean to talk about the red blood cells (RBCs) I will usually mention them specifically. I almost never discuss platelets because so far my platelets have stayed in normal ranges.

"my counts are down" - When I say my counts are down, I usually mean my WBC count and my absolute neutrophil count (ANC) are low and so I have to be careful about infection. See neutropenia for more infomation.

"my counts are up" - When I say my counts are up, I usually mean that my WBC and ANC have returned to acceptable levels.


Common Abbreviations

q. - quaque - every (q.2 = every two hours, q.3 = every three hours, etc.)
q.h. - quaque hora - every hour
q.d. - quaque die - every day
b.i.d. - twice a day
q.i.d. - quater in die - four times a day
p.o. - per os - by mouth
n.p.o. - nothing by mouth
p.r.n. - pro re nata - as needed
S, sig - Signa - indicates the directions to be written on a prescription

IV - intravenous - into a vein
IM - intramuscular
SC, subq, sub-Q - subcutaneous

CBC - Complete Blood Count
WBC - white blood cell
ANC - absolute neutrophil count
RBC - red blood cell
HGB - hemoglobin
HCT - hematocrit
PLT - platelet

Works Consulted

Jones, Betty Davis. 1999. Delmar's Comprehensive Medical Terminology: A Competency-Based Approach. Albany, New York: Delmar.

Thomas, Clayton L., ed. 1997. Taber's Cyclopedic Medical Dictionary. 18th ed. Philadelphia: F.A. Davis.


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