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MCAS: Effects on eyes, ears, nose and mouth

MCAS patients suffer a variety of symptoms in systems localized to the head, often without well characterized explanations.  Eye, ear, sinus, nasal and mouth symptoms are often documented.
Generic irritation of the eyes, including dry eyes and/or itchy eyes, are the most common ophthalmologic complaint.  Excessive tearing is also common.  Like many other symptoms, the tearing can be occasional or chronic.  Redness, irritation of the sclera (the white part of the eye), the eye lid, and conjunctivitis can all affect one or both eyes.  Tremors and tics of the lid are sometimes found.  When particularly bothersome, patients sometimes seek treatment with botulinum toxin (Botox).  This treatment is at first successful, but the issue later resurfaces.
Difficulty in focusing in both eyes is particularly common when suffering other MCAS symptoms.  Despite seeking ophthalmologic explanations for these symptoms, most patients have no obvious cause of their inflammation.  32% of MCAS patients report eye issues. 
Symptoms affecting both anatomy and function of the ears are not atypical.  Irritation of the outer ear is unusual, but middle ear irritation, resembling an infection, is extremely common.  These “infections” often occur frequently and are resistant to antibiotic treatment because they are, in fact, the result of sterile inflammation. 
Hearing abnormalities are often found in MCAS patients.  They include hearing loss, ringing of the ears, and sensitivity to sound.  This is thought to be from sclerosis of the innter ear bones or tympanic membrane, which has been known to occur coincidentally with mast cell disease since the 1960’s.  Deterioration of the canal hairs and auditory nerve is also suspected in some patients.  Tinnitus is likely from mediator release causing overstimulation of the hair cells and auditory nerve fibers.  The most common finding by audiologists is sensorineural hearing loss of unclear origin.
Mast cells are densely concentrated in the cavities and passages of sinuses and in the nose.  Congestion, inflammation, ulceration, sores and pain are all common.  MCAS patients often have a heightened sense of smell with systemic reactions possible from an offending scent.  Unprovoked nose bleeds sometimes occur, which is thought to be from increased local concentration of heparin.
Pain in the mouth and lips is a frequent complaint.  Like so many other MCAS symptoms, it can be focal or diffuse, mild or disabling.  It is often found with leukoplakia, but yeast infection is not found.  Distorted sense of taste, especially where things often taste of metal, is common.  Ulcerations and sores often present.  While on preliminary examination they resemble herpes sores, they almost never are in MCAS patients. 
MCAS is associated with burning mouth syndrome, which is exactly what it sounds like.  The mucosa is normal on biopsy.  Mast cell mediator therapy can relieve pain, sometimes very quickly. 
Evidence of angioedema is often seen in the mucosa of the cheeks, tongue and lips.  Patients often undergo evaluation for hereditary angioedema.  While they are sometimes found to have decreased levels of C1 esterase antigen or function, it is not low enough to account for the angioedema.  This finding is often a red herring. 
Dental decay, often despite excellent dental hygiene, is being reported with increasing frequency.  It can be a lifelong issue or sudden onset.   There are several reasons suggested for this, but none definitive. 

Afrin, Lawrence B. Presentation, diagnosis and management of mast cell activation syndrome.  2013.  Mast cells.

Constitutional symptoms of MCAS

Constitutional symptoms are any symptoms that affect the function of several systems at once.  They are often nonspecific and can be attributed to many causes, complicating diagnosis. For many people with MCAS, the constitutional symptoms present first and with the greatest frequency.

Fatigue and malaise (the feeling of being “out of it”) are the most common symptoms reported in MCAS patients.  While many patients with these symptoms remain functional, for some, it can be truly, severely disabling, with some patients sleeping for the majority of the day.  Dr. Afrin has referred to stories of “patients in their twenties acting like they are in their eighties.”  Chronic fatigue syndrome, in which patients have severe fatigue unrelated to exertion, not relieved by rest and unrelated to other medical conditions, has been tentatively linked to mast cell activation by Dr. Theoharides. 

I see a lot of discussion about whether or not fevers are part of MCAS.  It depends which researcher is reporting information.  Castells feels strongly that fevers are not part of MCAS symptomology, while Afrin and Molderings feel that they are.  They report that intermittent elevated temperatures are not unusual.  These temperatures are low-grade temperatures, with frank fever being quite rare.  MCAS patients often report constantly feeling cold, though chills and shaking is less common.

I know that one of the ways I can tell my mast cell disease is ramping up is by severe night sweats.  This is apparently common in most presentations of mast cell disease.  As such, many MCAS patients have severe, unprovoked sweating, often overnight, sometimes not.  Some patients report a circadian rhythm.  Furthermore, this sweating is often accompanied by swollen or tender lymph nodes.  When these two symptoms are taken together, usually infection or lymphoma is suspected.  Once these are ruled out, patients are often left with no relief for this frustrating symptom.

Some patients report lack of desire to eat.  Some report quickly feeling full (early satiety.)  In some of these patients, the root cause is a swollen spleen.  A minority of MCAS patients lose weight due to their disease.

Weight gain in MCAS patients is far more common than weight loss.  It often begins suddenly and progresses rapidly, in the absence of dietary or activity changes.  This is partially due to the fluid dynamics of edema due to mast cell activation.  Less often, weight gain is from ascites (free fluid in the abdomen) or serositis, inflammation of the serous tissues, including the pleura (tissue lining the lungs), pericardium (the compartment containing the heart and origination of the large vessels connecting to the heart) and the peritoneum (tissue lining the abdomen.) 

However, the gain in adipose (fat) tissue seems to be responsible for most of the persistent weight gain.  Some patients gain more than 50kg in a year despite significant caloric restriction and frequent exercise.  Many people (and their providers) often attribute their worsening symptoms to the gained weight.  Some people undergo bariatric surgery and despite initial losses, regain the weight, with no improvement of other symptoms.

Pruritis (itching) is very common in MCAS.  Its presentation is varied; episodic or constant; local or diffuse; migratory or not; tolerable or disabling.   

The hallmark of MCAS is that patients invariably present with a collection of “sensitivities.”  These include severe or bizarre reactions to virtually anything, including drugs, food and environemental triggers.  Environmental triggers can be due to the presence of common allergens, physical (such as heat), electrical (such as generation of electrical charge when brushing hair) and even osmotic.  Exposure to harmless microorganisms can cause severe reactions.  Summers are often difficult for MCAS patients due to heat and increased UV exposure, while spring and fall are difficult due to pervasive pollen.  Triggers can cause reactions when the patient touches, inhales or ingests them. 

Though less of a problem than heat, exposure to cold can trigger a hyperadrenergic response that will fuel mast cell activation.  Care must be taken to avoid temperature extremes on either end of the spectrum.

Drug sensitivities are often found to be due to an inactive ingredient in the formulation.  Compounding is an important tool for MCAS patients.  Lactose monohydrate and potato are common fillers for MCAS patients.  Reconstitution at time of use with water is also not uncommon.



Afrin, Lawrence B.  Presentation, Diagnosis and Management of Mast Cell Activation Syndrome.  2013.  Mast Cells. 

Gastrointestinal manifestations of SM: Part 1

Gastrointestinal symptoms are among the most common in SM, with up to 80% of patients experiencing them regularly.  When averaging figures from many studies, about 51% of SM patients have abdominal pain, 43% have diarrhea, and 28% have nausea and vomiting.  11% of SM patients have GI bleeding, usually in the upper tract.  Other GI problems common in SM include steatorrhea (excess fat in the stool), malabsorption, swollen liver, swollen spleen, free fluid in the abdomen and portal hypertension.  GI distress in SM can be severe and often mimics Irritable Bowel Disease or Zollinger-Ellison Syndrome.
Abdominal pain in SM generally has two types.  The first is epigastric dyspeptic pain, found in the upper abdomen, and is associated with ulcer disease and oversecretion of stomach acid.  Despite early reports that peptic ulcer disease is rare in SM patients, more recent studies have repeatedly disproven this idea.  On average, about 23% of SM patients have peptic ulcer disease.  Ulcers in SM patients with dyspeptic pain are often found on endoscopy.  In one study, 19% had a duodenal ulcer, while 25% had severe duodenitis.
The other type of GI pain is characterized by lower abdominal cramping.  Generally, one type is more prominent in a patient than the other, and they rarely co-occur with equal intensity.
85-100% of SM patients demonstrate increased histamine production.  Histamine is known to stimulate acid secretion, so SM patients are generally expectly to produce too much acid in the stomach.  However, studies have shown a variety of conflicting results.  Some patients produce too much acid, some too little, and some in the normal range.  For those who overproduce acid, the levels can be extremely high, comparable to levels seen in Zollinger-Ellison Syndrome. 
Occasionally, achlorhydria, the absence of gastric acid, has been found in SM patients.  This is thought to be due to atrophic gastritis (chronic inflammation of the stomach mucosa) that leads to impaired signaling from the local cells; however, this is unproven. 
Multiple studies have attempted to link serum histamine levels with normal basal acid secretion.  In one study, all patients had high serum histamine, but 56% had normal basal acid secretion.  This finding can be attributed to several things, including measured histamine not being fully biologically active; circulating histamine level being less important to acid secretion rate than the level of histamine in the local mucosa.  High histamine has been found in the gastric mucosa of several SM patients with dyspeptic pain. 
Furthermore, the authors elaborated that the histamine levels might not have been high enough to stimulate acid production; that the H2 receptors on acid producing (parietal) cells may have become desensitized to such high histamine levels; or that parietal cells were unable to respond to the histamine signaling, for some other reason.  Of these possible explanations, desensitization is supported by previous research, though not in SM patients.
In a study of 21 patients, 30% of them showed abnormalities on upper GI barium studies.  19% had gastric nodules and 11% had gastritis or peptic disease.  Biopsies of gastric mucosa show increased histamine and increased inflammatory cell infiltration with increased mast cells.  GI symptoms did not correlate with mast cell counts.
Common endoscopic findings in SM patients with dyspeptic pain include: acid hypersecretion; peptic ulcer disease; thickened gastric or duodenal folds; nodular mucosal lesions; occasional altered motility; occasional urticarial lesions; and increased infiltration by inflammatory cells with or without increased mast cells.
Studies have shown that approximately 28% of SM patients have esophageal abnormalities.  These include esophagitis, reflux, varices (abnormally enlarged veins that may bleed) or motor uncoordination.  Difficulty swallowing was common in these patients.  When assessed, these patients showed that the lower esophageal sphincter did not close with enough pressure. 
Esophageal motor function was assessed in 16 patients by manometry.  In 15/16 patients, the esophageal body contractions were normal.  In 62% of these patients, the lower esophageal sphincter function was abnormal.  75% of patients had reflux symptoms.  2/16 did not relax the esophageal sphinter during swallowing.
Esophageal varices have been reported in several SM patients.  The current rate of occurrence is listed as 2.5%, but this is likely an underestimation.
Jensen RT. Gastrointestinal abnormalities and involvement in systemic mastocytosis. Hematol Oncol Clin North Am. 2000;14:579–623.
Bedeir A, et al.  Systemic mastocytosis mimicking inflammatory bowel disease: A case report and discussion of gastrointestinal pathology in systemic mastocytosis.  Am J Surg Pathol.  2006 Nov;30(11): 1478-82.
Lee, Jason K, et al.  Gastrointestinal manifestations of systemic mastocytosis.  World J Gastroenterol. 14(45): 7005-7008.

Neurologic symptoms of mast cell disease

Mast cells are known to closely associate with nerve endings and to be important in neurotransmission.  This can translate into a variety of neurologic symptoms.
In 2011, a retrospective study on the neurologic symptoms of mast cell patients (171 SM patients, 52 CM patients, all adult) was published.  The following is a summary of the results.
Syncope (fainting) is a well-defined complication of mastocytosis, reported here in 14.3% of patients .  In these patients, evaluation revealed that the likelihood of epileptic involvement was likely low.  About 2/3 of patients who had fainting episodes also had loose stool, cramping, nausea, sweating and flushing accompanying the episode.  Prostaglandin D2 and histamine are known to cause low blood pressure and fainting in addition to GI symptoms.  Aspirin is thought to protect against acute vascular collapse and fainting, and sees use in tolerant patients for these purposes.   
16.6% of mastocytosis patients complained of back pain.  In all but one patient, the cause was determined to be multifocal compression fractures throughout the spine, including thoracic region.  Vertebroplasty, a procedure in which special bone cement is applied to the fractured vertebrae, has been suggested for symptom relief of these patients.  One patient was found to have back pain due to dense mast cell infiltration of the vertebrae.  In this patient, radiation therapy provided symptom relief.
35% of patients reported headaches.  Several of these patients met the criteria for migraines.  Mast cells have been implicated repeatedly in migraine pathology, and mastocytosis patients are more likely to suffer from them than the general population.  In response to mast cell degranulation, reactive changes have been noted in trigeminal nerve, the structure responsible for sensation in the face and activities like chewing.  Trigeminal neuralgia has been noted in some patients with mast cell disease.
This paper was also the first to find a link between mastocytosis and multiple sclerosis.  Two adults with ISM developed relapsing remitting MS, and a patient with isolated UP developed primary progressive MS.  Mast cells are known to associate with MS lesions, and mast cell activation can be detected in cerebrospinal fluid of MS patients.  This study found an MS frequency of 1.3% among mastocytosis patients, compared to 0.1% in the general population.
Lastly, an association has been found between overall mast cell burden and susceptibility to experimental autoimmune encephalitis (EAE.)
Smith, Jonathan H, Butterfield, Joseph H, Pardanini, Animesh, DeLuca, Gabriele, Cutrer, F Michael.  Neurologic symptoms and diagnosis in adults with mast cell disease.  Clinical Neurology and Neurosurgery 113 (2011) 570-574.