August 2014: Post summaries and take home points

Umbrella term for disorders in which body does not produce enough myeloid cells and the cells produced do not function correctly.
Myeloid cells are a type of white cells including eosinophils, basophils, neutrophils and mast cells.
MDS patients have low blood counts.
Sometimes asymptomatic.
Spleen is often swollen.
Bone marrow biopsy is diagnostic.
There are a number of causes of MDS.
Stem cell transplant may be considered in severe cases.
Transplant has 50% survival after 3 years.
Majority of MDS patients progress to acute myeloid leukemia (AML).
23% of SM-AHNMD have SM and MDS.

Urticaria pigmentosa (UP) and telangiectasia macularis eruptiva perstans (TMEP) are forms of cutaneous mastocytosis (CM).
CM is caused by dense infiltrates of mast cells in the skin.
Skin is the organ most likely to be infiltrated by mast cells.
Patients with UP or TMEP who do not have SM can still have symptoms affecting organs other than the skin.
CM patients can have shortness of breath, low blood pressure, nausea, vomiting, diarrhea and other mast cell symptoms.
Mast cell mediators release in the skin can move through the tissue and trigger other mast cells.
The more skin covered by rash, the more likely systemic reactions are.
Having systemic symptoms does not mean you have SM.
If you develop CM as an adult, you are likely to develop SM.
Chronic elevation of tryptase, expression of CD25 by skin mast cells or presence of D816V CKIT mutation can indicate SM will develop.
Systemic symptoms in CM are treated the same way as in SM or MCAS.
MCAS does not refer to a state of reactivity or severe symptoms.

SM is not cancer.
It is not cancer because the cells do not proliferative enough to endanger life.
Most SM patients have indolent disease, for which life expectancy is normal.
ASM has more features in common with cancer.
MCL is cancer.

Anticholinergics block the molecule acetylcholine from sending signals in the central and peripheral nervous sytems.
Blocking acetylcholine can cause many side effects, including:
Decreased GI motility
Dry mouth and throat
Dilation of pupils
Rapid heart rate
Visual disturbances
Urinary retention
Cognitive issues
Myoclonic jerks
A lot of antihistamines are anticholinergics.
Cyproheptadine, promethazine, desloratadine, loratadine, diphenhydramine, clemastine, doxepin, doxylamine, ipratropium, hydroxyzine and meclizine are anticholinergics.
Alprazolam, diazepam, ranitidine, prednisone and hydrocortisone may be anticholinergics.
Cetirizine and fexofenadine are not anticholinergics.

Many allergic conditions are exacerbated by menses.
Sex hormones influence mast cell activation and degranulation.
Mastocytosis patients often discontinue antihistamine and antimediator medications during pregnancy.
During pregnancy, 45% of mastocytosis patients had itching, 40% had flushing, 24% had GI symtpoms, 9% had anaphylaxis.
22% had worsened symptoms throughout pregnancy.
18% developed new symptoms.
33% had improved symptoms during pregnancy.
15% had complete resolution of symptoms.
All resolutions occurred during the first trimester and most lasted throughout the pregnancy.
Anaphylaxis during pregnancy was resolved without epinephrine.
45% had no change in symptoms during pregnancy.
Anesthesia and medications for labor were safe in mastocytosis patients.
Premedication at initiation of labor is recommended.
Rate of prematurity and birth complications were similar to general population.

Medications that block the H1 receptor increase dopamine release.
Histamine stimulates prolactin release via the H2 receptor, which inhibits dopamine production.
Histamine can increase metabolism of norepinephrine, serotonin and dopamine.
About 40% of serotonin released by mast cells.
Serotonin causes many GI symptoms.
Mast cells release dopamine.
Frequent mast cell activation decreases dopamine production.
Dopamine can be converted to norepinephrine.
Dopamine is responsible for cognitive alertness.
Norepinephrine is responsible for concentration and vigilance.
Increased histamine increases norepinephrine production and secretion.