Mast Cell Activation Syndrome; Postural orthostatic tachycardia syndrome; This literature marketed information has been received from the authors in a published article title as stated below and refers to a 23-year-old female patient. the patient had a history of recurrent diffusely migratory joint pain since age 10 and who had experienced her first syncopal event at age 15-years old, resulting in a foot fracture from the fall. Also, in adolescence, she began suffering unexplained fatigue and occasional episodes of (mostly orthostatic) dizziness and tachycardia. She was in this ("usual") state of health until she received her first first dose of unidentified Merck hpv vaccine administered, also reported as Gardasil (Lot #, expiration date, dose, route of administration and anatomical location of vaccine were not reported) for prophylaxis at age 18-years-old, which resulted in flu-like symptoms, hives, and itching within the next day and lasted about a week. She received the second dose of Gardasil injection six weeks later and, one day later, developed worsening of the initial post-Gardasil symptoms to the extent that she decided not to receive the third dose. She also began noticing some worsening of her prior fatigue and episodes of orthostatic dizziness and tachycardia, and the worsening of these symptoms steadily progressed over the next several years. Three months after the second injection, she developed new allergic reactions to various foods as well as gastrointestinal (GI) symptoms such as vomiting, abdominal pain, and daily nausea despite no apparent triggering exposures. At 19-years-old, she consulted a gastroenterologist for a new type of abdominal pain. She was started on omeprazole and esomeprazole for presumed gastroesophageal reflux disease (GERD), but these treatments did not improve any of her symptoms. She remained unable to digest vegetables and most other plant-based foods and was able to eat only meat, squash, and bananas, but she found this extremely limited diet helpful in terms of ameliorating some of her symptoms. Also, when she was 19 years old, the joint pains she had suffered for nearly a decade finally led to evaluation by a rheumatologist, who found she had a hypermobile cervical spine and a Beighton score of 9/9. She was diagnosed with hypermobile Ehlers Danlos Syndrome (hEDS); physical therapy was recommended. At this point her medical problems required her to take a leave of absence from college, and she began working as a full-time receptionist, but with significant fatigue. At 22 years old, she was evaluated by an allergist with skin testing, which was only borderline positive to only peanuts, dairy, coconuts, and egg yolk. For the orthostatic tachycardia, dizziness, and fatigue, she was referred for full autonomic function testing, which was positive for POTS and negative for small fiber neuropathy. Her chief complaints at the time of initial evaluation were chronic joint pain, GI dysfunction, and recurrent hives, all exacerbated by diet. She also reported pruritus and headaches from smelling fragrances and a rash from swimming in pools. Her joint pains were primarily in her ribs and right shoulder; she also could easily dislocate multiple joints. She also had been suffering severe neck pain, which also had developed shortly after the Gardasil injections at age 18 and had been steadily worsening ever since. At initial evaluation, she had lost 20 pounds over the prior 3-4 years due to her restrictive diet, which reduced her GI and allergic symptoms. She admitted to insufficient fluid intake on some days due to her GI symptoms. To try to address her orthostatic symptoms, she was consuming increased salt, which significantly helped. Trials of oral diphenhydramine 25 mg for her pruritus were not helpful. Also, at the initial evaluation at 23-years-old, she reported frequent and painful urination, nocturia, and heat intolerance (including difficulty taking hot showers, with symptoms including lightheadedness and weakness). She reported a mild sleep deficit (6-7 hours per night) and also admitted to anxiety. She was taking sertraline and had tried other selective serotonin reuptake inhibitors (SSRIs) in the past, but none of them were helping her anxiety. She was started on low-dose clonazepam to take on an as-needed basis, and this was somewhat helpful for her insomnia. She also noted her periods had been irregular since menarche. At the initial evaluation , she reported she could go walking and shopping for limited extents; fatigue was her main limiting factor. She had not been able to return to college.   Laboratory testing for MC activation was significant solely for an elevated serum prostaglandin D2 at 211 pg/ml (normal 35-115). She also was found to have a positive anti-nuclear antibody (titer 1:320, homogeneous pattern), a beta-2-glycoprotein-1 IgG elevated five-fold above the upper limit of normal, an anti-cardiolipin IgG elevated three-fold above the upper limit of normal, and anti-thyroglobulin antibodies elevated 2.5-fold above the upper limit of normal. Anti-platelet therapy for possible anti-phospholipid antibody syndrome was considered, but she was allergic to non-steroidal anti-inflammatory drugs (NSAIDs), including aspirin. She managed her symptoms with a very restricted diet, avoidance of environmental triggers of flares of her symptoms, and high intake of fluids and salt. She was unable to find a tolerable antihistamine regimen because she was reactive to lactose and could not easily find or access lactose-free commercial or compounded formulations of these drugs. Oral Cromoglicic acid (CROMOLYN) (200 mg four times daily), however, did significantly improve her oral mucosal tenderness and ulcerations and her flushing and pruritus, implying (given the poor absorption of this drug) that most of her dermatologic symptoms (and perhaps at least certain other symptoms, too) were the direct and/or indirect result of aberrant mediator expression by dysfunctional GI tract MCs.  Literature report:  Upon internal review the of Mast Cell Activation Syndrome (MCAs) was considered as medically significant.   This is one of several report from the same literature article.   A copy of the published article is attached as further documentation of the patient's experience.