(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 30 year-old man presented with progressive visual field defect, headache and nausea. He had a history of occipital area blunt head injury (hit by an iron pipe at work) three months before referral to our clinic. The initial diagnosis at the local clinic was brain contusion and concussion. On the initial X ray no skull fracture was detected. However, owing to a progressive visual field defect and dizziness, epidural hemorrhage was suspected. A burr-hole trephination for drainage was subsequently performed. Unexpectedly, the operating neurosurgeon found a tumor mass instead of hematoma. Although the biopsy sample was obtained, only H&E slides were made without ancillary immunohistochemical stains (IHC). He was then transferred to our hospital for further evaluation and more tissue was obtained. The patient had no history of malignancy. All laboratory findings were within normal ranges, except AST 67 U/L (Normal range: 14-40), ALT 164 U/L (Normal range: 8-46) and serum lactated dehydrogenase (LDH) 532 U/L (Normal range: 218-472). Serologic tests for hepatitis, syphilis, and HIV infection were negative. Magnetic resonance imaging (MRI) revealed an epidural mass, approximately 7.0x6.8x4.1 cm, with extracranial extension forming a coffee bean shaped mass crossing the parieto-occipital lobe dura (Figs. 1, 2 and 3). The epidural mass was hyperintense to isointense to gray matter on T2 weighted images (WI) (Fig. 1), isointense on T1WI (Fig. 2). Following contrast infusion, the epidural mass showed marked heterogeneous enhancement but the extracranial mass did not (Fig. 3). In view of the radiologic findings, a clinical diagnosis of meningioma was considered and the patient underwent a brain biopsy to confirm the nature of the brain lesion.

(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 30 year-old female with history of familial polyposis, status post transanal excision of rectal villous adenoma, and restorative proctocolectomy with ileoanal anastomosis and loop ileostomy for colonic polyposis. An upper gastrointestinal endoscopy was performed and demonstrated multiple gastric polyps in the fundus and body (Figure 1A and B). Representative biopsies from the gastric polyps were submitted for pathological examination.

(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 30-year-old male with a 2-month history of a right corneal abrasion when removing his contact lens. Initial bacterial and fungal culture results were negative, and when he returned for a follow-up appointment, he complained of increasing ocular pain, headaches, and vision loss. Physical exam revealed an abrasion that had failed to heal, leading to a purulent corneal ulcer. Ocular fluid was collected, and the patient was started on antibiotics for a suspected bacterial infection.

(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 30-year-old Chinese male presented with an 8 week history of headaches, visual changes, lightheadedness and balance problems. These symptoms were attributed to increased intracranial pressure secondary to obstructive hydrocephalus. Computed tomography (CT) scans demonstrated an iso-or slightly hyperdense mass within both lateral ventricles. The septum pellucidum was not seen well on imaging studies and the tumor was centered on the midline. Contrast enhancement was mild to moderate. An MRI scan revealed a large midline mass obliterating large portions of the lateral ventricles and giving rise to obstructive hydrocephalus and transependymal edema. The mass was isointense on T1 weighted imaging and contained calcification On T2 weighted images it was relatively isointense with cortex (Fig. 1 and Fig. 2). There was moderate enhancement after the administration of gadolinium. Postoperative MRI scan showed gross total resection and some blood. After radiotherapy, the nerval symptoms had lapse to. But repeated MRI scans in the following 12 months showed recrudescence in the MRI findings and patient had more nerval symptomatic. Finally, the patient died of hydrocephalus and brain edema 20 months after the surgery.

(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 30-year old man with a 30-pound weight loss in one month, poor appetite, and episodes of abdominal and back pain. He has had progressive pancytopenia over 1 month.

(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.)

Presentation and examination

(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 30-years old male patient had suffered from childhood epilepsy at the age of three years. He presented with multiple cutaneous angiofibromas, bilateral renal angiomyolipomas and a tumor of the liver that had not been biopsied. His family history was unremarkable; in particular, TSC history was negative.

(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 30-year-old woman presented to her GP with complaints of intermittently occurring joint pain in her wrists and ankles. Further questioning revealed that she had been experiencing occasional morning stiffness and a tingling sensation in her extremities. She denied any headache or constitutional symptoms beyond mild fatigue. She stated that she had been tested for ANA and rheumatoid factor in the past and they were both negative. Additional inquiry revealed that the patient has a positive family history for rheumatoid arthritis. On physical exam, the patient expressed mild tenderness at both wrists. The rest of the exam was non-contributory. The GP was concerned about a potential autoimmune disease process and ordered an erythrocyte sedimentation rate (ESR) and an antinuclear antibody (ANA) test. The results are listed in table 1. The GP then referred the patient to rheumatology.

(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 30-year old woman presenting with lower extremity edema during and following a pregnancy in 2005. She underwent a renal biopsy in 2005 which established the diagnosis of membranoproliferative glomerulonephritis-type III (Strife variant). She was treated with ACE inhibitors, but no steroids or cytoxic drugs over the next four years. In the initial biopsy, there were minimal chronicity changes with only one of twenty-six (1/26; 4%) glomeruli being globally sclerotic. Presently, the patient has nephrotic syndrome. Blood pressure is 110/70 mm Hg on anti-hypertensive medication. Pertinent laboratory data include: creatinine 0.6 mg/dl, BUN 13 mg/dl, urine protein 4.4 gm/24 hrs (4+ by dip stick), ANA-negative, ANCA-negative, hepatitis-B/C serology-negative, cryoglobulin screen-negative, urine sediment-inactive (no cells or casts). Kidneys are normal size by ultrasound. The clinical differential diagnosis includes: persistent/recurrent type-III membranoproliferative glomerulonephritis and a new glomerular cause of nephrotic syndrome.

(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 31 year old woman presented with worsening neck pain for 2 weeks. She was treated for muscle spasms at an urgent care clinic with muscle relaxants and narcotic pain medication, but had no relief of symptoms. On physical exam, she had focal tenderness in the midline at the base of the occiput and resistance to any motion of the neck. Routine laboratory examination was unremarkable. There was no associated history of trauma. CT scan showed a large, expansile, and destructive mass in the right clivus extending into the right petrous bone with associated right medulla effacement (Fig 1). Follow-up with MRI again showed a 5.0 x 3.0 x 3.0 cm expansile, destructive mass in the right clivus and along the right anterolateral margin of the foramen magnum/base of the skull (Fig 2).

(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 31-year-old man, with no family history of neuromuscular diseases, received muscle biopsy for slowly progressive muscle weakness. The first symptom he had was difficulty dorsiflexing his feet at age 20 years, which was followed by gradual development of gait disturbance. At age 27 years, he started using a handrail to climb up stairs. At age 28 years, he developed dysphagia for liquid, in addition to difficulty raising arms, which led him to have aspiration pneumonia later in the same year. At age approximately 30 years, he developed dyspnea on exertion. Arterial blood gas analysis revealed hypoxemia (65 mmHg, at room air) and hypercapnia (82 mmHg), with a vital capacity decreased to 780 ml, leading to the diagnosis of chronic type 2 respiratory failure, and non-invasive ventilation was started. At age 31 years, he was unable to walk without aid and required a wheelchair for long distances. Physical examination revealed moderate muscle weakness and atrophy in an asymmetric limb-girdle distribution, together with marked muscle atrophy in the tibialis anterior muscles and weakness in ankle dorsiflexion with Medical Research Council grade 1. Mild neck muscle weakness was also noted. Serum creatine kinase level was 375 IU/L (normal: <287 IU/L). Electromyography showed myopathic changes. Skeletal muscle CT demonstrated remarkable fat tissue replacement in the semitendinosus muscles (figure 1a, arrows) at the thigh level.

(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 31 year old male with an unknown past medical history. The police initially found him naked, confused, and acting violently. He was taken to the emergency department, where his initial vitals and physical exam were significant for a temperature of 38.2oC, heart rate of 112 beats per minute, blood pressure of 156/108, diaphoresis, mydriasis, dried blood in his nares, skin pop marks on his arms, and no focal neurological deficits. Pertinent laboratory studies are included in Table 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 31-year-old man was hospitalized due to retinitis and progressive personality changes that had started several weeks earlier. He was disorientated and had changes of affect with mood swings as well as signs and symptoms of dementia. Neuropsychologically the patient showed Balint's syndrome (paralysis of visual fixation, optic ataxia, and impairment of visual fixation) with anosognosia, visual and spatial agnosia, ideomotor and ideational apraxia, attention deficits and visual hallucinations. Electroencephalogram (EEG) showed non-specific abnormalities. The ophthalmological exam revealed retinitis with bilateral macular changes and partial atrophy of the optic nerves. Laboratory tests and cerebrospinal fluid (CSF) examinations were unremarkable. Magnetic Resonance Imaging (MRI) showed diffuse areas with high signal intensity in T2- weighted and FLAIR images involving periventricular and subcortical white matter of the occipital and parietal lobes. (Figures 1, 2). Furthermore, a focal 1cm mass lesion was detected in the sellar region. There was some clinical improvement with steroid treatment, but the patient refused further diagnostic procedures and was released to home.

(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 32-year-old woman was referred to the Department of Neurosurgery, University of Zurich with a newly diagnosed supradiaphragmatic mass in the right paravertrebral region involving the paraspinal aspect of T10-12 and the T11 nerve root. The patient had noted a 2 year history of intermittent thoracic and upper abdominal pain radiating to the right side. No medical consultation was obtained during this period. After experiencing nausea and an episode of increased abdominal pain, which radiated to the right trunk and shoulder region, the patient presented to an emergency unit. There was no significant past medical history and the family history was negative regarding malignancies. On neurological examination no functional deficits were detected. MRI of the thoracic spine showed a circumscribed, right paravertebral and retrocrural multilobulated, encapsulated tumor measuring 46 x 42 x 58 mm. The tumor occupied the spinal canal between T10-T12, shifting the spinal cord to the left, protruding into the neuroforamina T10-T11 and infiltrated the 11th and 12th rib (Figs. 1a, 1b, 1c, 1d and 1e). Intra- and paraspinal resection of the tumor was performed in collaboration with a team from thoracic surgery. The infiltrated T11 nerve root was resected as well as the facet joints of T10/11 and T11/12 and the rib head of T11. A posterior decompression and instrumented fusion T10-T12 was performed. The tumor was highly pigmented with a dark brownish-black discoloration (Fig. 1f). The postoperative course was uneventful. Because of the diagnostic uncertainty, FDG-PET of the entire body, cranial MRI, fundoscopy, and gynecological examination were obtained, but no primary lesion was found. At 6 weeks clinical follow-up, the patient noted a significant decrease in thoracic and abdominal pain. Postoperative treatment consisted of adjuvant radiotherapy (33 x 2 Gy = 66 Gy). The MRI follow-up at 3 months after the operation showed no residual or recurrent tumor tissue in the thoracic spine (Figs.1g, 1h, 1i and 1j). A 3 month follow up FDG-PET of the entire body was performed showing 3 lesions in the abdominal fat, highly suspicious of metastasis (Fig. 1k).

(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 32-year-old man without specific underlying disease suffered from intermittent headache for more than half a month. The pain was localized over left side temporal area and then transferred to left occipital area. It could be relieved with acetaminophen. However a severe headache episode, with repetitive vomiting, aroused him from sleep early one morning. He was sent to the emergency department with stable vital signs and clear consciousness. On examination, there was no anisocoria, limbs weakness, dysphasia, dysarthria, or palsy of cranial nerves.

(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 32-year-old man presented with a 7-month history of headache and 2-month visual loss. Neurologic examination was unremarkable except for low visual acuity, worse in the left eye. Magnetic resonance imaging showed symmetrical cortical lesions in the midline, affecting predominantly both cingulate gyri and the upper corpus callosum. Lesions appeared multifocal, often limited to the cerebral cortex, confluent with speckled appearance, high signal intensity in T1-weighted images (Fig. 1), isointense in T2, strong contrast enhancement (Fig. 2), hypoperfusion with low regional cerebral blood flow values. Multivoxel spectroscopy showed increased choline/creatine ratio (2.97). There was prominent symmetrical edema of centrum semiovale. No changes were found in the leptomeninges.

(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.)

NEUROPATHOLOGIC FINDINGS Brain sectioning revealed, apart from macroscopic findings easily identifiable as consequences of the subarachnoid hemorrhage in the past (multiple cortical infarcts, "coiled" basilar aneurysm etc.), three unusual yellowish microlesions in the left and right nucleus ruber (2mm and 4mm in diameter, respectively) and pons (<0.5mm in diameter). Histopathological examination showed that these lesions were of moderate cell density and had clearly defined, but irregularly borders (Figure 1). The Gomori silver stain revealed a well-established network of reticulin fibers surrounding these cells (Figure 2). The lesions consisted of ovoid to elongated cells that were positive for Vimentin, S100-protein (Figure 3) and myelin basic protein (MBP) (Figure 4) but did not react for 2',3'-Cyclic-Nucleotide 3'-Phosphodiesterase (CNP). These cells were intermingled with some lipid-laden macrophages. Within the lesions pre-existing axons seemed to be largely preserved as visualized with an antibody detecting neurofilament protein (NF) (Figure 5). The adjacent brain parenchyma showed reactive astrogliosis. The lesions did not react with antibodies staining for actin, desmin, EMA, synaptophysin, NeuN, Melan A, CD31, p53 or IDH-1. The proliferation index estimated with Ki-67 (MIB-1) was low (approximately 1%). It is worth mentioning that all three lesions were located in the proximity of small stage III infarctions.

(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 32-year-old man was admitted to the neurosurgery department due to progressive dizziness and weakness of the feet for a month. An MRI revealed a well-demarcated mass measuring 60x35x25 mm, obstructing the fourth ventricle with dilatation of the lateral ventricles, third ventricle and the aqueduct. The lesion showed contrast enhancement with heterogeneous low signal intensity on T1WI (Figure 1) and mixed heterogeneous low and iso-signal intensity on T2WI (Figure 2). Several foci of cystic change were noted. A gross total resection 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 is a 32 year old male who presented to the emergency department complaining of progressive fatigue and shortness of breath on exertion over a two to three month period. He denied any infection, bleeding or bruising. He reported consumption of one case of beer per day for ten years, but in the last four years had reduced his intake to one six-pack per day. Past medical history is significant for multiple gunshot wounds to the abdomen in the late 90s requiring resection of small bowel and colon, including the terminal ileum and cecum. This was followed by repair of a large ventral hernia in 2001. No outpatient medications and no known drug allergies. Physical exam showed mild scleral icterus, lungs clear to auscultation, heart regular rate and rhythm without murmurs, rubs, or gallops, abdomen with midline scar, liver palpable 2 cm below the left costal margin, and spleen not enlarged.

(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 37-year-old woman presented with the eye sight declined repeatedly for eight months and became more and more serious. On clinical examination, she had developed blurred vision but no focal neurological signs. Laboratory analysis showed the following: red blood cell (RBC) count, 2.59×1012/L; hemoglobin, 88.0 g/L; mean corpuscular volume (MCV), 106.3 fl; mean corpuscular hemoglobin (MCH), 35.0 pg; mean corpuscular hemoglobin concentration (MCHC), 330.0g/L; red blood cell distribution width (RDW), 29.0%; white blood cell (WBC) count, 15.9×109/L; 55% orthochromatic erythroblasts; platelet count, 92.0×109/L.