(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.)

We present a 36-year-old cognitively intact male, with history of work-related solvent exposure who consulted for headache, vomiting and fever in September 2009. Symptoms persisted in spite of antibiotic therapy. CT scan showed a hypodense image in the left parietal lobe. MRI revealed a parietal lesion hypointense on T1, hyperintense on T2, and FLAIR, without mass effect (Fig. 1a). Thoracic CT scan showed bi-apical interstitial infiltrates. Standard TB treatment was indicated along with steroids, obtaining a partial clinical response. Two months later, following steroid tapering, significant clinical deterioration was observed with fever, headaches and nausea. Patient was re-evaluated showing no changes on MRI. PCR testing for several microorganisms was negative. Differential diagnoses considered were: recurrent Meningitis NOS vs. vasculitis vs. ADEM (Acute Disseminated Encephalomyelitis). A new course of methylprednisolone was administered; after which patient requested voluntary discharge. In December 2009, patient returned with persistent fever and headache. A methylprednisolone bolus was administered and partial, transient response observed. At this time, the diagnosis considered was ADEM refractory to steroids, and treatment was switched to immunoglobulin therapy, which led to a complete clinical response. Once again, patient requested voluntary discharge, but had to be re-admitted later, due to headache, fever, mental confusion and aphasia in January 2010. New CSF PCRs ruled out viral diseases and TB. Other differential diagnoses considered included: Marburg's disease, CNS lymphoma and Neuro-Behçet's disease. The patient then suffered rapid clinical decline, developing limb weakness, somnolence and hyponatremia and died in January 2010.

(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 36-year-old woman was referred to our unit for subacute onset (within 2 months) of right eye ptosis and unreactive mydriasis. The patient complained of photophobia, right ocular dryness and progressive inability in focusing on images. A neurological examination at a local emergency room found incomplete III cranial nerve palsy. A CT scan was normal. The right fundus oculi evaluation with optic coherence tomography (OCT) showed papillary edema. Visual fields examination showed blind spot enlargement in the right eye. An MRI showed slightly T2 hyperintense tissue enlarging Meckel's cave and involving the carotid artery (Figs. 1a, 1b). The mass involved the right temporal dura, the cavernous sinus and extended into the right orbit through the superior orbital fissure (Figs. 1c, 1d). The right superior orbital fissure enlargement was well documented by an orbital CT scan (3D reconstruction, Fig. 1e). After Gd administration, it presented intense and homogenous enhancement (Figs. 1f, 1g) leading to the suspect of a lymphomatous or granulomatous lesion (neurosarcoidosis, Tolosa-Hunt syndrome). During the admission the patient underwent a complete serological investigation for infectious diseases and autoimmune disorders which resulted negative except for a slightly increased ACE level (57, n.v. = 8-52). Blood Calcium and parathormone (PTH) level were normal. The cerebrospinal fluid (CSF) biochemical analysis did not show any significant alteration and atypical lymphocytes were not found. Visual evocated potential showed normal latencies with increased cortical responses amplitudes. A chest CT scan showed only a small ground glass area in the apical segment of the right inferior pulmonary lobe. There were no radiological signs of interstitial abnormalities or mediastinal lymphadenopathy. A high dose corticosteroids (CCS) cycle was tempted without significant clinical improvement. After few days, the right eye ptosis consistently worsened and the patient developed right lateral gaze diplopia and hypoesthesia in the second trigeminal branch (V2) territory. After the CCS cycle a second MRI was repeated showing a diffuse increase of the lesion enhancement after Gd administration. It also involved the right muscle cone and the sheets of the right optic and trigeminal nerve through the oval foramen thus compressing the right carotid syphon. The mass infiltrated the left internal pterygoid muscle and extended in the left part of upper nasopharynx. Therefore, the patient underwent endoscopic endonasal biopsy performed through a bilateral anterior sphenoidectomy and a right transmaxillo-pterygoid approach to the pterygopalatine fossa.

(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 an approximately 30-year-old primigravida with an intrauterine dichorionic-diamniotic twin pregnancy. Prenatal ultrasound at 30 weeks gestation showed a multi-cystic mass without fetal parts suspicious for hydatidiform mole (twin A), and one live fetus with normal anatomy (twin B) with a corresponding enlarged, cystic placenta (placenta B). At 36 weeks gestation, the mother developed preeclampsia and preterm labor and delivered one live, morphologically normal female infant (twin B) weighing in the less than tenth percentile. The infant was transferred to the NICU after delivery for low birthweight and prematurity.

(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 36-year-old man, with personal history of a right parietal cranial injury, was admitted for an evaluation of a right parietal mass that had slowly increased in the nine years prior to this presentation. General examination disclosed nothing. Skull examination revealed a palpable pulsatile and soft swelling. Routine laboratory tests were unremarkable. Computed tomography (CT) and magnetic resonance imaging (MRI) of the head were obtained to delineate the large mass in the parietal region. MRI showed a prominent extracranial scalp vein in direct communication with the superior sagittal sinus, through a right parietal bone defect. CT scan showed an old fracture with osteomeningeal breach. There was no parenchymal abnormality. The lesion was heterogeneously intense on T2- (Figure 1), T2-Flair (Figure 2) and T1-weighted images (Figure 3). Doppler sonography found vascular structures composing this lesion. Due to the worsening pain at the site of her swelling, a total resection was performed. Intra-operatively, the lesion was defined by the surgeon as a blood-filled sac within the pericranium and directly overlying the bone suggesting an angioma.

(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.)

FD is a 36-year-old white woman with a history of an inherited genetic disease, diagnosed in 1999 when she was found to have a low leukocyte alpha-galactosidase enzyme level. She also has a remote history of headaches, tinnitus, vertigo, acroparesthesias, and angiokeratomas. There is extensive family involvement with this particular genetic disease, and those affected include her father, her teenage son, and two sisters. Her father died at age 49 from complications of cardiovascular and renal disease. The patient has no reported history of diabetes or hypertension; her recent blood pressure is 112/74 mmHg. An echocardiogram showed a normal left ventricular size and an ejection fraction of 60%. Pertinent laboratory values include: BUN 13 mg/dL, creatinine 0.6 mg/dL, hemoglobin 13.2 gm/dL, hematocrit 36.6%, and glucose 81 mg/dL. Urine analysis shows trace protein with no cells. The patient has no peripheral edema. She had microalbuminuria with urine albumin 4.2 mg/dL.

(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 patient is a 36 year-old male who is 216 days status post-kidney transplantation due to hypertension induced kidney failure. He had high creatinine (Cr) values with difficulties controlling his serum Cr which reached a value of 3.1 mg/dl. At that time, the patient was found to shed BK virus in his urine (BKV DNA: 7.7E05 copies/ml), however, no BKV DNA was detected in plasma. A renal allograft biopsy was performed. (Figure 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 36-year old male presented to the hospital with an ear infection. Laboratory studies drawn in the emergency department demonstrated a pancytopenia including neutropenia. He was admitted to the hospital where he underwent an extensive workup including viral testing for hepatitis B, hepatitis C, and HIV, all of which were negative. Imaging of the sinuses was negative for acute or chronic sinusitis. His past medical history was significant for testicular cancer diagnosed at the age of 23. He is status post left orchiectomy and radiation therapy. He was in his usual state of health until approximately 3 months ago when he started having episodes of night sweats. Physical examination was significant for splenomegaly that measured approximately 3 fingerbreadths below the costal margin. The peripheral blood smear demonstrated anisocytosis, ovalocytes, polychromasia and tear drops. Atypical lymphoid cells were identified with rounded nuclear contours and hairy cytoplasmic projections (Figure 1). Platelets were reduced.

(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 36 year-old African American male with a history of end stage renal disease secondary to IgA nephropathy. He underwent kidney transplantation in 2001, which subsequently failed in 2005 due to rejection. Allograft nephrectomy was performed in 2006 because of hematuria. He had been on peritoneal dialysis prior to his transplantation and wished to resume this method of renal replacement after the failure of his transplant. A dialysis catheter was placed in November 2005. Three months later, he presented with abdominal pain and cloudy peritoneal drainage. On physical exam, he was afebrile with normal vital signs. He had peri-umbilical tenderness with guarding and rebound tenderness. Peripheral white blood cell count was 10,600/cu mm with a normal differential. CT scan of the abdomen showed no free or loculated fluid collections. A sample of peritoneal fluid was sent for culture (Figs. 1, 2 and 3)

(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 female from Brazil presented with paresthesia and cramping in the left calf. She also reported transient loss of strength in the left arm. Neurological examination revealed paresthesia on the entire left side of her body. No clinical abnormality was noted on physical examination, including breast and lymph node examination. During hospitalization, she presented sensorimotor seizure of the left arm and leg. Cerebral MRI showed a rolandic right lesion of postcentral gyrus with FLAIR hypersignal (Figure 1), heterogeneous enhancement and edema around the lesion (Figures 1 and 2). Laboratory tests, including blood cell count and CSF puncture, did not find any abnormality. Cerebral biopsy for diagnosis 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.)

A 37-year-old woman had bilateral blurred vision with hazy vision gradually from periphery to center for two months. There was mixed horizontal and vertical diplopia. Ophthalmologic treatment did not help. We she came to us, an Humphrey visual field test disclosed bilateral temporal hemianopia. CT showed hyperdensity and heterogeneously enhanced sellar lesion with size 2.57 x 1.96 x 3.63 cm and supra-sellar extension. MRI T1 showed sella tumor with isointense signal mixed with the hyperintense part (Fig 1a). MRI T2 scans showed compression of the optic chiasm. With contrast, there was heterogeneous enhancement in the tumor. The clivus showed a heterogenously enhancing lesion was noted on T1 with contrast (Fig 1b).

(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 36-year old right-handed female patient in the 21st week of pregnancy presented to the Neurology emergency department due to double vision, hypoesthesia on the right side of her face, headache, nausea and weight loss. The symptoms had started 4 months previously, when she was going through an IVF (in vitro fertilisation) procedure, with nausea and weight loss. She became pregnant a few weeks after the symptoms started. Neurological examination revealed right abducens nerve palsy and sensory loss in the area of the right maxillary and mandibular nerve. MRI, T1 weighted sequence, showed multiple lesions in the ventricular system, and one in the region of the right trigeminal nerve, which could have been metastases (Figures 1A and 1B - arrows pointed the tumors). The complete blood count showed mild anaemia. A lumbar puncture was performed, which revealed normal opening pressure, mild pleocytosis (6 leucocytes) and slightly elevated proteins. There were no malignant cells in the CSF, chest X-ray, and abdomen and breast ultrasound were unremarkable. The neurosurgeon suggested a biopsy of the lesions next to the trigeminal nerve but only after the delivery. The patient did not consider abortion. Her neurological condition slowly deteriorated and a caesarean section was performed in the 30th week of pregnancy, followed immediately by a biopsy of the lesion in the region of the right trigeminal nerve. She gave birth to a girl weighed 1400g. After the delivery, the patient's condition started to deteriorate at a more rapid pace, with a worsening of headache with vomiting, disorientation and gait instability. A head CT scan showed obstructive hydrocephalus and open ventricular drainage was performed, after which the headaches subsided. She started treatment with radiotherapy. Seven weeks after delivery and 10 months after the beginning of her symptoms, she became unconscious with unreactive pupils and was admitted to the intensive care unit. A CT scan showed hematocephalus and obstructive hydrocephalus. She died the same day.

(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 37-year-old African American woman with a history of poorly treated HIV infection, diagnosed in 2001, with progression to AIDS. A recent CD4 count showed 7 cells / cubic millimeter with a viral load of 745,000 copies / milliliter. She presented to the emergency department with fever up to 102.3 degrees Fahrenheit and a cough productive of yellow sputum with no hemoptysis. She denied any recent weight loss. She denied ever having a positive PPD, but could not remember when she was last tested. She had been admitted 6 months previously for similar symptoms, and all cultures were negative except for the stool, which was positive for non-tuberculous mycobacteria.

(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 female presented with occipital headache, muscle weakness and paresthesia in the right limbs over 3 months. Magnetic resonance imaging showed a 5 cm solid, contrast-enhancing mass in the left lateral ventricle and adjacent parietal white matter with midline shift, ventricular compression and hydrocephalus (Figure 1). After surgical resection, she was submitted to radiation therapy for 4 months and did well for 3 years, when progressively growing thoracic wall nodules appeared. In the last 2 weeks she complained of paraparesis and hypoesthesia in the lower limbs. Computerized tomography showed lesions in the left clavicle and scapula, sternum and T11 vertebra, the latter causing spinal cord compression (Figure 2). Laminectomy was followed by radiation therapy for the thoracic lesions and chemotherapy. The patient evolved with improvement of muscular strength and relapsing episodes of thoracic pain, controlled with medication. So far there is no radiological evidence of intracranial recurrence. NEUROPATHOLOGICAL FINDINGS

(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 man presented with a 2-month history of headache and balance impairment. He also complained of nausea and two episodes of vomiting a few days before admission. His past medical history was unremarkable. Neurological examination showed mild left sided ataxia.

(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.)

37 year-old woman with no significant past medical history presents to a dermatologist for a "mole" on her left calf. The lesion has been present for approximately 6 months and besides the appearance has not been problematic. The patient has been otherwise asymptomatic. The patient's physical exam was within normal limits except for a 2 x 2cm erythematous, indurated nodule on her left medial calf. The patient's laboratory studies, including a complete blood count, a basic metabolic panel, erythrocyte sedimentation rate, rheumatoid factor, and antinuclear antibodies, were all within normal limits. A CT scan of the chest, abdomen, and pelvis was normal. The lesion was excised.

(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 female neonate was delivered at 38 weeks gestation to an 18 year-old, gravida 1, Native-American female whose antepartum course was notable for crystal methamphetamine and tobacco use early in pregnancy. Prenatal care had been initiated at 11 weeks of gestation, and an ultrasound performed at approximately 20 weeks revealed findings interpreted as a large posterior fossa cyst with mass effect. The cerebellum had not been well visualized, although the impression was that some cerebellar tissue was present. These features were overall felt to reflect a Dandy-Walker cyst. Additional ultrasonographic impressions included a probable porencephalic cyst on the right side, ventriculomegaly, possible agenesis of the corpus callosum, and overall significant absence of brain parenchyma in the right hemisphere. Serial follow-up ultrasound evaluations were performed at approximate 4 week intervals, demonstrating essentially the same intracranial ultrasonographic findings. Of note was that other organs showed appropriate growth progression. At delivery by Caesarian section, the posterior aspect of the neonate's scalp was noted to be covered by a thin, tense membrane, which ruptured during the procedure. Apgar scores were 7 and 9 at 1 minute and 5 minutes, respectively, and death occurred within hours of birth.

(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.)

Our patient is a 38-year-old female with a past medical history significant for celiac sprue. She adheres strictly to a gluten-free diet. She is on no medications other than a multivitamin, and she has no family history of illnesses. She had her first child in 2001 (female) via normal spontaneous vaginal delivery and without complications.

(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 38-year-old man, status 8 months post resection of his anaplastic oligodendrogioma of the right frontal lobe presented for a monitoring magnetic resonance imaging (MRI). The imaging studies revealed a slight interval increase of the minimally enhancing nodular mass consistent with the recurrent tumor (Figure 1). The patient received 6 cycles of temozolomide. Past medical history included frontal sinus infection and temporal mandibular joint dysfunction.

(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 38 year-old female, known case of diabetes insipidus presented with a progressively deteriorating left sided weakness, headache and bilateral papilledema. Her lipid profile was normal. Magnetic resonance imaging revealed a large right-sided frontoparietal mass (8.5x5.8x4.7 cm) with smooth displacement of adjacent brain parenchyma and mild midline shift (Figures 1 and 2). A smaller (1.4x1.2x0.6 cm) yet similar lesion was identified on the right side of the falx cerebri. Radiologic diagnosis of meningioma was made. The patient underwent right frontoparietal craniotomy. A small amount of tissue was sent to pathology for intraoperative diagnosis followed by total resection of the large frontoparietal lesion. The lesion in the falx cerebri was not resected in view of its small size and location. No adjuvant therapy was administered.

(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 39-year-old-woman had suffered from a moderate grade fever of unknown origin and a headache for 9 months. A previous hospital could not find the cause of her symptoms; therefore, she came to our hospital. At the first visit to our hospital, she had no signs of meningeal irritation and no palpable lymph nodes in the neck or supraclavicular regions. And then, she complained dysesthesia of her limbs and decreased visual acuity in the left eye. The laboratory data showed hypoproteinemia, hypoalbuminemia, hypochromic microcytic anemia, positive antinuclear antibody, and elevated serum levels of CRP (13.12 mg/dl), IgG (2080 mg/dl), IgA (622 mg/dl), and Interleukin-6 (IL-6) (73.2 pg/ml). CSF protein level was elevated (126 mg/dl), there was an oligoclonal band and IgG index was increased, but anti-aquaporin 4 (AQP4) antibody was negative. Cell count in CSF was normal. MRI detected an enhancing mass in the left cerebellar hemisphere (Figs.1A, 1B). In addition, there was a mildly enhancing lesion in the cervical spinal cord (Figs. 1C, 1D). But intraorbital region and optic nerve had no abnormalities. The patient had a suboccipital craniotomy for tumor resection. The tumor was connected to the choroid plexus at the foramen of Magendie without dural attachment, and was totally removed. The postoperative course was excellent, and no further fever appeared from the day after surgery. Immediately after the resection, dysesthesia of her limbs and visual disturbance in the left eye was also improved. The enhancing lesion in the cervical cord was vanished. Serum levels of CRP (0.1 mg/dl), IgG (1180 mg/dl) and IL-6 (0.8 pg/ml) were decreased and the anemia was improved after surgery.