Hemophagocytic lymphohistiocytosis (HLH) is a rare but life-threatening syndrome resulting from excessive immune activation. Secondarily, HLH is often associated with autoimmune disease, infection, and malignancy. The most common infectious trigger is Epstein-Barr virus (EBV) infection. HLH is rarely triggered by parvovirus B19. We discuss a case of a 62-year-old male who presented with multi-organ failure with presumed septic shock who eventually was diagnosed with HLH, with positive parvovirus B19 deoxyribonucleic acid (DNA) polymerase chain reaction (PCR). Prompt treatment with dexamethasone resulted in significant clinical resolution.

Symptomatic gastrointestinal (GI) involvement of melanoma is rare, however, it is a frequent autopsy finding in patients with primary cutaneous melanoma. We present a case of metastatic cutaneous melanoma with initial asymptomatic jejunal involvement as found on a positron emission tomography (PET) scan, with subsequent duodenal perforation.A 69-year-old man presented to the hospital with a three-week history of worsening headache, dizziness, and vomiting with a history of Clark level III malignant melanoma that was completely excised from the right flank three years ago at the hospital. A magnetic resonance image of his brain revealed a subacute right-sided cerebellar hemorrhage adjacent to a 1-cm nodule. He underwent a right suboccipital craniomy with resection; the biopsy of which revealed metastatic malignant melanoma. A staging positron emission tomography (PET) scan revealed areas of increased uptake of fludeoxyglucose (FDG) in the left lower lung and left upper quadrant of the abdomen abutting the small bowel. Subsequent enteroscopy revealed a 40-mm cratered jejunal ulcer with heaped edges; the biopsy of which also revealed malignant melanoma. Since he had widespread disease, abdominal surgery was deferred, and treatment with ipilimumab and radiotherapy to the brain was initiated. He presented three months later with acute abdominal pain and diarrhea. A computed tomography scan of his abdomen revealed free peritoneal air, and an exploratory laparotomy revealed a mass at the antimesenteric border of the duodenum with a biopsy consistent with melanoma. The perforated area was resected and an end-to-end anastomosis was performed. Unfortunately, our patient had a postoperative intracranial hemorrhage and was referred to palliative care.Our case portrays how malignant melanoma may metastasize insidiously and widely and present as a catastrophe. Melanoma involvement in the GI tract is a poor prognostic marker. Our case offers a unique illustration of both the occult and manifest gastrointestinal involvement of melanoma and underscores the importance of clinical suspicion in patients with a history of melanoma who present with unexplained GI symptoms.

Carcinoembryonic antigen (CEA) has been shown to be associated with tumor burden in patients with colorectal cancer. However, it is also elevated to a significant degree in a number of other malignant and non-malignant conditions. We report a case of reversible CEA elevation in a patient using lithium for bipolar disorder.A 58-year-old female with a longstanding smoking history and a past medical history of chronic obstructive pulmonary disease (COPD), bipolar illness, hypothyroidism, and obesity was found to have an elevated CEA level of 11.2 ng/ml (normal level <5 ng/ml) in the workup for postmenopausal bleeding. Her history was not positive for malignancy of colorectum, ovaries, thyroid, or breast.  She underwent a large number of imaging and endoscopic studies to evaluate for colorectal, breast, ovarian, and lung cancer; however, it did not reveal any evidence of malignancy. Upon review of her medications, she reported that she had recently started lithium for her bipolar illness. We followed up her CEA level while her dose of lithium was reduced from 450 to 300 mg per day. Her CEA level decreased from 25 mg/dl to 6.1 mg/dl and remained stable over the course of the next eight months.Our case is the first case report that identifies lithium as a potential cause of reversible CEA elevation. The underlying mechanism is yet to be elucidated, but it underscores the importance of investigating the medications as part of the workup.

Malignant infiltration of pia and arachnoid mater, referred to as leptomeningeal carcinomatosis (LMC), is a rare complication of gastric carcinoma. The most common underlying malignancy in patients with LMC are leukemia, breast cancer, lymphoma, and lung cancer.We report a case of gastric adenocarcinoma that presented with LMC in the absence of overt gastrointestinal signs or symptoms. A 56-year-old Hispanic woman presented to the hospital with a three-week history of intermittent headaches and visual blurring. An initial brain imaging showed infarction in the distribution of right posterior inferior cerebellar artery (PICA) along with communicating hydrocephalus. She underwent ventriculoperitoneal (VP) shunt placement with improvement in her symptoms. Two months later she presented again with deterioration in her mental status. Imaging studies and cerebrospinal fluid (CSF) analysis confirmed the diagnosis of LMC. Further studies determined the primary tumor to be signet ring cell gastric adenocarcinoma. However, she did not have any preceding gastrointestinal symptoms. In light of the poor prognosis, the patient's family proceeded with comfort care measures.Our case portrays a rare presentation of gastric adenocarcinoma with LMC without other distant organ metastatic involvement. It also illustrates the occult nature of gastric carcinoma and signifies the importance of neurologic assessment of patients, with or at risk of gastric carcinoma. ​It also raises a theoretical concern for VP shunt as a potential conduit of malignant cells from the abdomen to the central nervous system, which may serve as an important susbtrate for future research.

Less than four percent of patients with hypothyroidism develop ascites. Ascites as the presenting feature of hypothyroidism is uncommon, hence diagnosis is often delayed. Once it is diagnosed, treatment of hypothyroidism leads to quick clinical improvement in ascites. We report a case of a female patient who presented with ascites secondary to severe hypothyroidism and discuss the diagnostic characteristics of the ascitic fluid in myxedema ascites on the basis of literature review.

Dientamoeba fragilis (D. fragilis) is an anaerobic intestinal protozoan parasite that has been associated with irritable bowel syndrome (IBS)-like symptoms. We report a case of post-infectious IBS caused by D. fragilis treated successfully with metronidazole.A 33-year-old African American male with an unremarkable past medical history was seen in the office with a three-month history of intermittent, generalized, crampy abdominal pain with bloating and flatulence without associated weight loss. He visited Mexico for his honeymoon four months ago. Initial lab work was normal. Dietary changes including fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet and loperamide were prescribed with the presumptive diagnosis of IBS; however, his symptoms persisted. Three samples of stool for ova and parasites (O&P) were positive for D. fragilis. The patient was treated with metronidazole for 14 days. Repeat fecal O&P were negative. Upon follow-up, the patient’ symptoms substantially improved with a resolution of abdominal pain and flatulence.Infection caused by D. fragilis may be symptomatic or asymptomatic. It is transmitted by the fecal-oral route. Symptoms include abdominal pain, bloating, and alteration of bowel movements, resembling IBS. The diagnosis is made via the detection of D. fragilis trophozoites in appropriately fixed and stained stool samples or by a polymerase chain reaction. Treatment options include tetracyclines, paromomycin, metronidazole, and Iodoquinol. Further epidemiologic studies may help in elucidating the association between D. fragilis and IBS.

Liddle syndrome is a rare form of autosomal dominant monogenic hypertension manifested as an early onset of resistant hypertension with either no response or suboptimal response to conventional antihypertensive therapy. If there is a delay in diagnosis, uncontrolled hypertension can lead to end organ damage. To our knowledge, aortic dissection has not been reported in association with this disease. We report a case of a dissecting aortic aneurysm occurring in association with Liddle syndrome.​

KCNQ1 gene mutation has a well-known association with long QT syndrome (LQTS). However, recent studies suggest that it may be implicated in intestinal neoplasia. We present a 27-year-old Hispanic man with a known history of LQTS secondary to KCNQ1 mutation, who presented with painless jaundice. Endoscopic retrograde pancreatic cholangiography revealed a prominent ampulla, with histology consistent with ampullary adenoma with high-grade dysplasia. Further endoscopic studies did not suggest familial adenomatous polyposis. To date, this is the index case of duodenal ampullary adenoma in the setting of KCNQ1 mutation.