Never bet against occam, p.43
Never Bet Against Occam, page 43
Chronic atrial fibrillation
See Atrial fibrillation.
Chronic lymphocytic leukemia
“Kron´-ik limf´-oh-sit´-ik loo-keem´-ee-uh.” Chronic lymphocytic leukemia (CLL) is a typically slowly progressing leukemia (many patients don’t actually run into clinical problems from it (and thus don’t need treatment for it) until many years after diagnosis) in which there is excessive production of the “lymphocyte” type of leukocyte, or white blood cell. Similar to the relationship between chronic myelogenous leukemia and acute myelogenous leukemia, CLL’s progression tends to be much slower (over many years) than the rapid (over weeks to months) progression of the far more deadly acute lymphocytic leukemia (ALL).
Chronic myelogenous leukemia
“Kron´-ik my´-el-oj´-en-us loo-keem´-ee-uh.” Chronic myelogenous leukemia (CML) (also commonly referred to as chronic myeloid leukemia) is a type of MPN in which there is excessive production of the “granulocyte” type of leukocyte, or white blood cell, but CML tends to progress slowly (over years), in contrast to the rapid (over weeks to months) progression of the far more deadly acute myelogenous leukemia (AML).
Chronic myeloproliferative neoplasms
See Myeloproliferative neoplasms.
Cimetidine
“Sim-et´-ih-deen.” The first marketed histamine H2 receptor blocker, and it’s inexpensive and still commonly used (the most recognized trade name in the U.S. is Tagamet), but it has more drug-drug interactions than most other H2 blockers (which also tend to be quite inexpensive).
Cladribine
“Klă´-drih-been.” A chemotherapy (cancer-cell-killing) drug, typically given as a short IV treatment or a shot under the skin every few weeks, that benefits some mastocytosis patients, but it certainly doesn’t cure the disease, it only works in a portion of patients, and in those patients in whom it works, it tends to kill only a portion of the malignant mast cells and that improvement tends to last for only several months. Like most chemotherapy drugs, cladribine is too toxic (i.e., causes too many side effects) to be able to take such treatment indefinitely, so most patients take a few to perhaps several rounds, or cycles, of treatment and then have to stop. It’s important to note that chemotherapy drugs generally are thought to be helpful in truly cancerous diseases (where one cell type or another is growing out of control), and that describes more aggressive forms of mastocytosis pretty well, but it does not describe mast cell activation syndrome (MCAS), so – at least at present – there doesn’t seem to be any sensible role for chemotherapy in the treatment of MCAS.
Claritin
“Klahr´-ih-tin.” Claritin is the most commonly recognized trade name for loratadine in the U.S.
Clavicles
“Klav´-ih-kulz.” Clavicles is the official anatomical term for what everybody else knows as collarbones.
Clonazepam
“Kloh-naz´-eh-pam.” Clonazepam is a type of benzodiazepine drug useful for settling some symptoms in some patients with mast cell disease. It binds with benzodiazepine receptors in the body, including benzodiazepine receptors on the surface of the mast cell, and when that binding takes place, it tends to lead to some quieting of the mast cell’s activation. See Benzodiazepines for more information.
Clonidine
“Klon´-ih-deen.” Clonidine is an old, inexpensive, oral anti-hypertensive medication (its best recognized trade name in the U.S. is Catapres) that binds with the alpha-2 adrenergic receptor on blood vessel walls and results in relaxation of the vessel wall and thus a lowering of blood pressure.
Clostridium difficile colitis
“Klos-trid´-ee-um dif´-ih-sil kohl-īt´-is.” Clostridium difficile colitis is inflammation of the intestinal tract from an infection from Clostridium difficile bacteria. (“Clostridium difficile,” of course, is such a mouthful that it always gets abbreviated, at least in speaking, as “C. diff.”) (By the way, I’m italicizing it because the names of microorganisms are supposed to be italicized in writing.) C. diff. is a “bug” that one tends to get as a consequence of having other, normal bugs in the intestinal tract wiped out as a side effect of antibiotic therapy given for infection (in the intestinal tract or elsewhere) for some other bug. Its most prominent symptom is diarrhea that can become so severe as to be life-threatening.
Coagulopathy
“Koh-ag´-yoo-lop´-uh-thee.” Although this term technically refers to any disorder of the clotting system, it’s often taken by many doctors to refer just to those clotting system disorders that result in excessive bleeding, leaving the term “hypercoagulability” or “hypercoagulable state” to refer to just those clotting system disorders that result in excessive clotting.
Colitis
“Kohl-īt´-is.” This is a general term that simply means inflammation (from any cause) in some or all of the colon (i.e., the large intestine). As mast cell activation disease (both mastocytosis and MCAS) very commonly causes inflammation in multiple parts of the body, it shouldn’t be surprising that colitis is a common issue in MCAD.
Colon
“Kohl´-on.” Colon is the medical/anatomical term for the large intestine.
Colonoscopy
“Kohl´-on-osk´-oh-pee.” A procedure in which a scope is inserted through the anus and rectum and then advanced through the colon to provide the doctor (usually a gastroenterologist, but sometimes a surgeon) a view of the entire interior surface of the colon. Colon cancers and inflammation sometimes can be discovered this way. This is a common test to be performed when the patient has symptoms (for example, blood in the stool, or otherwise mysterious abdominal pain or chronic diarrhea) suggesting the possibility of disease of some sort in the colon.
Computed tomography
Computed “toh-mŏ´-graf-ee,” abbreviated CT, also referred to as computed tomographic scanning or CT scanning. A method of X-raying the body (or, in truth, any object) to produce a series of images that represent serial slices through the body, allowing you to see much of what lies inside the body without having to cut open the body, which is sort of what a normal X-ray does, except a standard X-ray picture superimposes all of the “slices” in an imaged field into one relatively blurred picture, whereas CT scanning separates out those slices to provide far clearer pictures which, in a sense, actually provides a three-dimensional picture of the imaged field since the depth of where any particular finding resides in the imaged field corresponds to which particular slice(s) show that finding.
Constitutive activation
“Kon-stich´-ih-tiv ac´-tih-vay´-shun.” Programmed, constant activation of some protein, molecule, or system. A good thing when the thing that’s constantly activated is supposed to be constantly activated, but quite a bad thing when the thing that’s constantly activated is not supposed to be constantly activated.
Continuous positive airway pressure
Another mouthful of a term, and thus almost always abbreviated CPAP, usually pronounced “see-pap.” This refers to both a technique in general, as well as to the machine that applies the technique, to treat obstructive sleep apnea (OSA). CPAP involves placing a mask (usually held in place by straps around the head) over the patient’s nose, or nose and mouth, taking care to seal the edges of the mask against the face. The mask is then connected to a hose that in turn is connected to an air pump that pumps air through the hose and mask, and therefore into the patient’s airway, at a predetermined pressure. Because the fundamental problem in OSA is collapse of the airway which prevents inhalation of air, pumping air in will prevent that collapse and thus keep air moving smoothly into the lungs. Of course, when the patient exhales, that stream of air has to fight against the air being (constantly) pumped in, but the human diaphragm which powers lung inhalation and exhalation is a powerful muscle and can easily do this. Many modern CPAP machines have the “smarts” built in to sense the various phases of the respiratory cycle to increase pressure during inhalation, decrease pressure during exhalation, and, of course, always maintain some level of pressure to ensure the airway remains open and doesn’t collapse. Nevertheless, the pressure of the machine’s air supply/flow against the patient’s lungs at rest, not to mention the machine’s pressure against exhalation, makes CPAP feel weird when first applied, and there are some who simply cannot tolerate it, but it is safe and effective therapy that has helped millions of people with OSA rid themselves of the severe morning fatigue and headaches that come from OSA. This situation is a perfect example of one of the key principles in managing mast cell disease, namely, that it’s imperative to ensure, as best as is reasonable to pursue, that no more-obvious issue than mast cell disease is causing any given specific symptom or abnormality, since regardless of whether that more-obvious issue is ultimately rooted in mast cell disease or not, that more-obvious issue needs to be treated with whatever standard therapy exists for that issue. To be sure, if the more-obvious issue indeed is ultimately rooted in mast cell disease, then it’s likely that the absolute best outcome with respect to that issue will come from applying not only standard therapy for that issue but also effective therapy for the underlying mast cell disease. Nevertheless, whatever the established standard therapy is (e.g., CPAP) for that issue (e.g., OSA) absolutely remains the “starting point” for effective treatment of the issue, even in a mast cell disease patient.
Coproporphyrin
“Koh´-proh-por´-fir-in.”
Coronary artery disease
“Kor´-oh-nār-ee” artery disease, typically abbreviated CAD.
Corticotropin releasing hormone
“Kor´-tih-koh-trohp´-in” releasing hormone, typically abbreviated CRH.
Coryza
“Kor-ī-zuh.” The $400 medical word for discharge of clear fluid from the nose, i.e., when your nose is “running,” you’ve got coryza.
COX1
“Kox” one. One of the types of cyclo-oxygenase enzymes involved in manufacturing certain inflammatory mediators. See Cyclo-oxygenase.
COX2
“Kox” two. One of the types of cyclo-oxygenase enzymes involved in manufacturing certain inflammatory mediators. See Cyclo-oxygenase.
Creatine kinase
“Kree´-uh-teen kī´-nās,” often abbreviated CK.
Cromolyn
“Krohm´-oh-lin.”
Cronkhite-Canada Syndrome
“Kron´-kīt” (just like the famous old newscaster, which this syndrome has nothing to do with) Canada Syndrome.
Cyropyrin-Associated Periodic Syndrome (CAPS)
“Krī´-oh-pir-in” associated periodic syndrome.
Cutaneous
“Kyoo-tayn´-ee-us.” The medical word referring to the skin. A cutaneous lesion is a skin lesion. A subcutaneous injection is an injection under the skin.
Cyanosis (also cyanotic)
“Sī´-uh-nohs´-is.” A bluish appearance to the skin, almost always due to insufficient oxygen in the blood for one reason or another.
Cyclobenzaprine
“Sī´-kloh-benz´-uh-preen.” A muscle relaxant medication, often prescribed when patients complain of muscle pain and aching that the doctor thinks might be due to excessive muscle tightness/tension, or spasm. Its most recognized trade name in the U.S. is Flexeril.
Cyclo-oxygenase (COX)
“Sī´-kloh-ox´-ih-jen-ās” (COX: “kox”). COX (which appears to have been officially renamed by biologists as PTGS (prostaglandin-endoperoxide synthetase, “prost´-uh-gland´-in end´-oh-per-ox´-ih-dās sinth´-eh-tās”) since I first learned about it in medical school longer ago than I care to reveal here, except that to this day it still seems to be popularly referred to (amongst members of the medical profession, anyway) as COX) actually refers to a small group of enzymes (“small” as in “2,” namely, COX-1 and COX-2) which are found in many (actually, most) types of cells in the body and which are responsible for formation of a large class of important biological molecules called prostanoids (“prost´-uh-noidz”) including – yes, you guessed it – the prostaglandin D2 molecule that’s relevant to diagnosis of mast cell disease. In general, prostanoids stir up inflammation, so medications that inhibit their formation have anti-inflammatory effects. Most of the non-steroidal anti-inflammatory drugs (NSAIDs; see the entry for such in this dictionary) temporarily inhibit both COX-1 and COX-2, though the classic NSAID aspirin permanently inhibits both (at least until the aspirin is gone from your system and your cells begin making more COX-1 and COX-2). There also are the relatively new “COX-2 inhibitors” (such as celecoxib; its sister drug rofecoxib, or Vioxx, was pulled off the market when it was found to cause too much heart trouble), which of course inhibit only COX-2, which sometimes provides some advantages over the less expensive combined COX-1/COX-2 inhibitors.
Cyclophosphamide (Cytoxan)
“Sī´-kloh-fos´-fuh-mīd.” A chemotherapy medication commonly used to treat various types of cancer and, somewhat less often, various types of immune system disorders, especially autoimmune conditions. Its most recognized trade name in the U.S. is Cytoxan (pronounced “sī-tox´-an”).
Cyclosporine
“Sī´-kloh-spor´-in.” This is a medication, available in both oral and IV forms, which suppresses the immune system. It’s used very occasionally to treat mast cell disease but far more following transplantation, when you want to keep your immune system from perceiving that wonderful new organ you just got as a foreign invader in your body and attacking and destroying it.
CYP2C9
“Sip”-2-C-9. Before I can explain CYP2C9, I need to back up and explain CYP450 (“sip” four fifty). There is a large family of enzymes in the body, called the CYP450 enzymes, which are responsible for breaking down and otherwise detoxifying lots of substances we take into our bodies, including medications. This family of enzymes is part of the human body’s very wide and complex array of mechanisms which enable us to survive for decades in environments that often are pretty harsh, assaultive, and toxic. The CYP450 enzyme family includes many members, generally called isozymes (“ī´-soh-zīmz”) with designations such as 2C9 or 2D6 or 3A4 (and thus also called CYP2C9 or CYP2D6 or CYP3A4), each of which is able to detoxify one specific chemical class of toxins or another. You can easily imagine, then, that if one of your CYP450 isozymes is not working properly, there may well be consequences (and by “not working properly,” I mean either working poorly or even working too well). Sometimes a CYP450 isozyme won’t work properly because of an interaction with a medication, but in the majority of the situations where a CYP450 isozyme is found to not be working properly, the cause is traceable to a mutation in the patient’s gene that codes for the protein that is that isozyme. These mutations are called polymorphisms (“pawl´-ee-morf´-izmz”). (Often these polymorphisms are inherited, but sometimes they spring up out of the blue at the time of conception, after which they may be handed down to later offspring.) What are the potential consequences of a CYP450 isozyme not working properly (whether due to an interfering medication or a polymorphism)? Well, if the isozyme is working too well (i.e., a “fast metabolizer”), any medications that normally are broken down by that isozyme will be broken down faster than usual, meaning that to get the usual amount of effect out of the medication, the dosing may need to be higher and/or more frequent. On the other hand, if the isozyme is working poorly (i.e., a “poor metabolizer”) (which sometimes means it’s not working at all), then any medications that normally are broken down by that isozyme will be broken down more slowly, if at all – which in turn means that the medication will build up in the body, not only causing more of the intended effect but quite possibly also causing a number of unintended effects ordinarily not seen unless unusually high levels of the medicine are seen (like in an overdose). Although many medications interfere with CYP450 isozyme functioning, and although CYP450 polymorphisms are far more prevalent in the human population than most doctors are aware, it is difficult to diagnose CYP450-related problems because it is difficult to suspect CYP450-related problems. Why? Principally because the number of medication/CYP450 interactions is vast and can’t possibly all be remembered, and because medical training about CYP450-related problems consists of about a minute’s worth of in-class lecturing relatively early in the decade or so of training most doctors get (and with no follow-up clinical training), and because the more troublesome CYP450-related problems – the poor-metabolizing ones – tend to result in relatively slow (over weeks to months) build-up of an unmetabolized medication, meaning the toxicities of such build-up show up relatively slowly, and by the time those toxicities become clinically apparent, it’s a long way down the road from when the medication was started and thus would require a lot of (typically uncompensated) effort to very carefully dig through the patient’s chart, and through the medical literature describing the actions of all of the patient’s drugs, to finally pin down that a CYP450-related problem is the likely cause of the toxicities, at which point the CYP450-interfering medication needs to be adjusted or stopped and/or special, typically expensive blood testing needs to be done (usually requiring 2-4 weeks to get a result) to prove that a CYP450 polymorphism actually is present. Little wonder, then, that the vast majority of people with CYP450-related problems never get diagnosed as such, eh? And let me make clear that I’m no better than any of my colleagues at recognizing such problems. Yes, I’ve caught some CYP450-related problems relatively early, but others I’ve caught only in the nick of time to save the patient’s life, and there have been a few times I didn’t catch it until I came to be involved in the patient’s care too late to save the patient from permanent injury or death – and I’m quite confident there have been lots more times that I never caught it all because I never suspected it, for all the reasons mentioned above. Final lesson of the day on CYP450-related problems: although most such problems that result in toxicities from build-up of unmetabolized medications tend to cause slow such build-ups and thus slow-to-emerge toxicities (over many weeks or months), sometimes the build-ups and toxicities develop more quickly (over mere days to perhaps a few weeks), and because adverse medication reactions within days to a few weeks can be caused by mast cell disease, too, it can be even more difficult than usual to suspect CYP450-related problems in a patient with mast cell disease. In a mast cell disease patient in whom adverse medication reactions emerge within minutes to hours of taking a new medication, it’s more likely the patient’s dysfunctional mast cells improperly reacting to the new medication that’s causing a reaction seen within minutes to hours of trying an “offending” or “triggering” medication, but if the reaction doesn’t start to show up until days to a few weeks into the medication trial, it’s almost impossible to tell, on clinical grounds alone, whether the problem is a real adverse reaction to the active ingredient or a triggering of the patient’s mast cell disease (by either the active ingredient or one of the fillers or dyes in the medication) or a problem related to the metabolism of the drug (whether a CYP450 isozyme issue or an issue with some other drug-metabolizing enzyme involved in the metabolism of that drug). (So at this point you’re wondering, “Is there no limit to the complexity that has to be dealt with in mast cell disease patients?” And the answer is “No.”)
