(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

This 4-year-old girl presented to the emergency department complaining of fever and pain in the lower extremities with refusal to bear weight. On four occasions a hip x-ray was performed, and she was sent home with pain medications. No laboratory studies were performed. She presented again with the above symptoms and weight loss (weight 13.8 kg, <10th percentile for age.) She was admitted and worked up for possible malignancy. Laboratory studies including a bone marrow biopsy were performed.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 4-month-old female infant presented with a growing extracranial mass at the left frontotemporal region. Covered with intact skin, the lesion measured 3.5 x 3 x 3 cm; it was well-defined, bony hard in consistency, and fixed to the underlying skull. There were no other abnormal symptoms, and routine laboratory tests were within normal limits. The mass appeared sclerotic on skull film. Computerized tomography scan of the brain (Fig. 1) showed a homogeneously enhancing expansile bone tumor. The lesion caused widening of the lower part of the left coronal suture, just above the orbital roof. The patient underwent left frontotemporal craniotomy, and the mass was found to involve the frontal and temporal bones, around the inferior limb of the coronal suture, adherent to the underlying dura. The orbital roof and apex were also affected. The lesion was totally resected. The immediate postoperative course was uneventful.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 50-year old male with a history of type 2 diabetes, hypertension and a nontoxic goiter, was referred to a neurosurgical center due to a newly diagnosed hypothalamic mass. He had been previously admitted to his local hospital due to somnolence, inadequate behaviour and memory disturbances of about two-week duration. His blood glucose levels were regularly measured and were known to be normal through the preceeding weeks. A full endocrinologic check-up showed normal levels of all measured hormones and no alteration of their circadian rhythms.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 50-year-old man was followed for 4 years for a radiological diagnosis of meningiomas of the falx cerebri. He was admitted for an evaluation of the mass that had slightly increased in the last year prior to this presentation. General examination disclosed nothing. Computed tomography showed a large hypodense well-circumscribed mass attached by a broad base to the falx cerebri (Figure 1a). On MRI of the head, the tumor measured 3.5 cm and appeared hypointense on T1-weighted images and hyperintense on T2-weighted images. It was uniformly enhanced by Gadolinium contrast injection (Figure 1b) and hyperinstense on T2-Flair (Figure 1c). There was no parenchymal abnormality. The radiologist interpreted the imaging as suspicious for a meningioma. Due to the recent enlargement of the tumor, a total resection was performed. Intra-operatively, the lesion was defined by the surgeon as a lesion with a dural-based attachment suggesting a meningioma.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 50-year old Caucasian female patient presented for follow up in February 2007, several months after a left tympanomastoidectomy (July 2006) with ongoing complaints of fullness, fluttering, and hearing loss in her left ear. In June 2007, an MRI of the internal auditory canals was performed and incidentally suggested a pituitary mass. A dedicated pituitary MRI was repeated in July 2007 and showed a well-circumscribed 8mm area of less-enhancing tissue within the left pituitary (arrow, Figure 1) without obvious invasion of the cavernous sinuses or impingement on the optic chiasm.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 50-year-old female with no significant surgical history presented with a left posterior thigh mass. Magnetic resonance imaging studies demonstrated a 3.0 cm peripherally enhancing, lobulated mass that was centered in the subcutaneous tissue of the left distal thigh.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient was a 50-year-old man who presented with six months of abdominal pain, a 15-20 pound weight loss, night sweats and chills. Biopsies of the stomach revealed Burkitt lymphoma with retroperitoneal involvement. A staging bone marrow biopsy was negative for tumor. However, tumor burden was large and chemotherapy was elected. Cyclophosphamide and prednisone were given prior to the start of a chemotherapy regimen consisting of ifosfamide, mesna, methotrexate, leucovorin, vincristine, Ara-C, etoposide and Decadron. Intrathecal methotrexate was given twice. The patient developed fevers shortly before completion of this protocol. Pan-cultures remained negative. The patient tolerated chemotherapy until the final day (7 days after the last intrathecal dose of methotrexate) when he became confused. Over the following day this evolved into an agitated delirium. Neurologic exam later that day showed decerebrate posturing in an intubated, comatose patient with intact brainstem function. Head CT showed no evidence of hemorrhage and MRI showed minimal findings on diffusion and FLAIR images. EEG showed changes suggestive of drug effect but no significant focal abnormalities. CSF showed normal glucose and protein levels and no white blood cells. Clinically, the patient failed to improve over the next three days. MRI imaging studies were repeated and showed severe changes. The patient expired 12 days after symptom onset.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 50-year-old man with a two-month history of severe back pain being treated for shingles complained of mild headaches and sudden-onset diplopia for two weeks. His medical history is significant only for heavy alcohol use. Neurologic examination revealed ptosis and complete plegia of his right eye. The remainder of the exam was within normal limits. MRI revealed a 3.0 x 2.9 x 1.5 cm circumscribed mass centered on the sella turcica extending into the superior aspect of the clivus and into the right cavernous sinus. It demonstrated mild, somewhat heterogeneous enhancement with intermediate signal intensity on T1 and was isointense on T2-weighted images (Figures 1 and 2). No normal pituitary gland was identified. Serum prolactin, follicle stimulating hormone and growth hormone levels were within normal limits.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 50 year old lady presented to the clinic with mild occipital headaches, vomiting, swallowing difficulties and ataxia which had developed over a period of 3 months and were progressively worsening in severity. No significant past medical history was noted and she was not on any regular medication. The social and family histories were unremarkable. Examination demonstrated a GCS 15/15, horizontal nystagmus, intention tremor and disdiadokokinesis. Fundoscopy revealed bilateral papilloedema. No cranial nerve dysfunction was identified. MR imaging revealed a 4th ventricular enhancing mass with significant obstructive hydrocephalus and a degree of tonsillar herniation (Fig 1).

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 51-year-old man was discovered deceased on the bathroom floor of his home. He had no history of hypertension or other chronic disease. Due to the lack of significant medical history and the unexpected nature of the death, an autopsy was ordered by the county coroner. At autopsy, no apparent thoracic or abdominal cause of death was identified. The decedent did have mild cardiomegaly (525 grams) with left ventricular hypertrophy (2.4 cm). No acute ischemic changes were seen grossly. Sectioning of the coronary arteries showed minimal luminal narrowing and no evidence of acute thrombotic occlusion.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

51-year-old woman presented with chronic fatigue and weakness for approximately 6 months. A CT scan showed a large left renal mass. The patient underwent radical nephrectomy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 51 year-old right-handed female presented with a two-month history of double vision and numbness around her left ear. Her walking became unsteady and she progressively developed left facial and tongue numbness, left-sided hearing loss and a left facial droop. In the two weeks prior to presentation she complained of headaches with associated nausea and vomiting.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 52 year old man with an unremarkable clinical history started to complain of daily somnolence, unusual irritability and some memory lapses. A few months later, he had fever and developed confusion with myoclonic jerks of the left limbs. Upon admission a diagnosis of encephalitis was made. MRI FLAIR images (Figure 1 A, B) showed cortical and sub-cortical abnormal signal intensity in parasagittal posterior frontal and anterior parietal regions, compatible with ischemic damage in watershed areas. On coronal T1-weighted image (insert in Figure 1A) cortex was hyperintense for petechial hemorrhage. Multivoxel Proton Magnetic Resonance Spectroscopy (1 H-MRS) demonstrated lactic acid in the lesions (Figure 1C, arrows). The CSF showed 10 white cells / ml with normal protein and glucose. He was treated with antibiotics, acyclovir, steroids and immunoglobulins and improved so that he was discharged to a rehabilitation facility. The patient could play chess and walk around with the help of a walking frame.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The case is received in consultation. The patient is a 52-year-old female who presented to her primary care physician with presyncopal symptoms, nausea, and vomiting. A further history of right flank pain, intermittent hematuria, and weight loss of approximately 20 lb. over the past year was also elicited. Her past medical history includes alcoholic cirrhosis, diabetes mellitus type II, and thyroid surgery with thyroid hormone replacement therapy.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 52 year old female came with intermittent left facial paresthesia/ hyperesthesia and swelling since 3 weeks.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient is a 52-year-old male who presented to gastroenterology with a 3 week history of abdominal pain. He described the abdominal pain as sharp, mid upper abdominal pain that occurred immediately after meals and was not relieved by over-the-counter antacids or pain medications. He had some heartburn, but denied other gastrointestinal symptoms. A colonoscopy was performed and showed a large intraluminal mass in the proximal ascending colon. A biopsy was performed but was not representative of the mass. A right hemicolectomy was performed.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

The patient was a 52 year old male with a history of Cushing's disease, initially diagnosed at the age of 18. At that time, his symptoms included increased weight, purple abdominal striae, diabetes mellitus, and polydipsia. He underwent a resection of a pituitary microadenoma at another hospital. However, due to persistently high cortisol levels following the surgery, he later underwent a bilateral adrenalectomy. Following the operation, he began hydrocortisone therapy, lost weight, and was able to maintain glucose control without diabetes medications. At the age of 32 his diabetes recurred, but he was able to maintain good glucose control up until age 51 at which time his HbA1C was greater than 7. He also had visual problems with significant reduction in right peripheral vision and moderate impairment in left. Testing revealed a greatly elevated serum ACTH at 5,082 pg/mL (normal is 9 - 46 pg/mL), but serum cortisol within normal limits 4 ug/dL. There was no pigmentation of the skin. MRI scans found a large, contrast-enhancing mass in the pituitary fossa with extrasellar extension into the right cavernous sinus and displacement of the parasellar carotid posteriorly (Figs 1 and 2). The patient underwent endoscopic endonasal approach for debulking of the mass.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 52-year-old man was admitted with dyspnea and found to have pneumonia. He was treated and discharged but continued to be dyspneic, with new symptoms of fever, night sweats, and weight loss, leading to readmission one month later.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

A 53-year-old woman presented with a growing mass in the left lumbar region. The patient had become casually aware of it ten years ago. Since then she performed radiological and clinical follow-up; she refused surgical resection. In 2009 a cytological examination had displayed mesenchymal cells without nuclear atypia. In the last year the tumor had been growing and had become symptomatic with pain during physical activity. Clinical examination revealed an unmovable swelling on the left lumbar region with intact skin. MRI showed a 9x4x5 cm T1 hypointense and T2 hyperintense mass, with a strong and heterogeneous enhancement after contrast infusion and a hypointense central core. It extended from the body of the second to the fifth lumbar vertebra. CT scan of the chest also revealed four pulmonary nodules enhancing with contrast, two of which were hypermetabolic during the whole body PET-CT scan (max SUV 2.7 and 2.4). The patient underwent surgical resection of the lumbar lesion which was easily removed with sharp dissection from the surrounding muscle fibers.

(This case study was added to OER Commons as one of a batch of over 700. It has relevant information which may include medical imagery, lab results, and history where relevant. A link to the final diagnosis can be found at the end of the case study for review. The first paragraph of the case study -- typically, but not always the clinical presentation -- is provided below.)

DL is a 53-year-old male with past medical history significant only for hepatitis C. He was discovered one afternoon convulsing and unresponsive in a cemetery. He was initially taken to UPMC Northwest, where he was intubated for airway protection and loaded with phenobarbital 1 gram IV to treat the diffuse muscle spasms. His vital signs at this time included a temperature elevated to 39.0oC, a blood pressure of 143/74 mm Hg, a heart rate of 120 beats per minute, respiratory rate of 17 breaths per minute, and an oxygen saturation of 100%. An arterial blood gas demonstrated profound combined metabolic and respiratory acidosis with pH 6.55 (reference range 7.35-7.45), pCO2 92 mm Hg (reference range 35-48 mm Hg), pO2 368 mm Hg (reference range 83-108 mm Hg), HCO3 10 mEq/L (reference range 22-26 mEq/L). He was transferred to UPMC Presbyterian for further management.