A case of McLeod phenotype of neuroacanthocytosis brain MR features and literature review.

Huntington's disease and neuroacanthocytosis may present similar clinical and MRI features. It is important to differentiate these findings since treatment and prognosis vary vastly between them. The aim of this article is to familiarize radiologists with the differentiating features of Huntington's disease and various diseases comprising neuroacanthocytosis. A 40-year-old Indian man with extrapyramidal symptoms was referred for MRI. The clinical diagnosis was Huntington's disease, but there were a few atypical clinical features such as a history of biting the tongue, tics, marked hyporeflexia and lower limb muscle wasting. MR showed atrophy of the caudate nucleus and putamen with iron deposition in the basal ganglia, which can be seen in Huntington's disease and in neuroacanthocytosis. An increased blood acanthocyte level was subsequently confirmed. Further work-up revealed increased serum creatine phosphokinase levels, normal serum lipoprotein levels and depressed K cell antigen activity on serological studies, confirming the diagnosis of McLeod syndrome. McLeod syndrome is one of the distinct phenotypes of neuroacanthocytosis. Neuroacanthocytosis is a group of disorders with increased serum acanthocyte counts and neurological involvement. Various causes of neuroacanthocytosis are discussed. It is important to consider the possibility of neuroacanthocytosis when features typical of Huntington's disease are encountered on imaging.

Diagnostic criteria of tuberculous sarcoidosis.

With the object to strengthen the clinical status of tuberculous sarcoidosis, we present in this article, the case records published in internationally recognized journals by specialists. From review of clinical material, we have also formulated a table that defines diagnostic criteria of tuberculous sarcoidosis.

Aspergilloma in sarcoidosis.

This is a case report of a 48-year-old man, followed up for nearly 30 years who initially developed sarcoidosis at the age of 18 that went into remission after 8 years of treatment. Ten years later, he developed sputum-positive tuberculosis and was cured with anti-tubercular treatment. Following this, there was progression of sarcoidosis to stage IV fibrocystic disease. Ten years later, he had massive hemoptysis during which time, aspergilloma was detected in a sarcoid cystic cavity.

Dorsal dermal sinus with intramedullary abscess formation.

Dorsal dermal sinus, a congenital abnormality associated with spinal dysraphism, can serve as a path for spread of infection inside the spinal thecal sac with its sequelae. Intramedullary abscess formation is an uncommon complication and only about 20 cases have been reported in the English literature. We report MR appearances of three new cases.

Caudal regression syndrome with sacral rib: MRI features.

Caudal regression syndrome (CRS) involves improper and incomplete development of distal spinal segments. Sacral rib is an unusual entity, where an accessory rib arises from the sacral vertebral segments. Very few cases have been described in the English literature. We present the case of a 3-year-old girl presenting with urinary and bowel incontinence and difficulties in walking with left-sided sacral rib, terminal cord syrinx, and caudal regression syndrome, involving sacrococcygeal segments, diagnosed on MRI. The association is not well illustrated in previous reports.

Rasmussen encephalitis associated with Parry-Romberg syndrome.

Parry-Romberg syndrome is a rare disorder associated with unilateral facial atrophy involving skin, subcutaneous tissue, skeletal muscle, and bone. Occasionally, there is CNS involvement with epilepsy being the most common CNS manifestation. The authors report a child with Parry-Romberg syndrome with a course strongly suggestive of Rasmussen encephalitis. The boy underwent hemispherectomy, and pathology showed the typical findings of Rasmussen encephalitis, suggesting that these two conditions may share common etiologic factors.

MRI in ankle tuberculosis: Review of 14 cases.

We reviewed the MR imaging features of ankle tuberculosis and determined the role of MR in its diagnosis. A retrospective analysis of 14 cases of ankle tuberculosis imaged with MRI was performed. Plain radiographs were also reviewed where available, and the imaging characteristics were noted. We also reviewed the medical records in order to assess the impact of the imaging findings on management of these patients. Magnetic resonance imaging is extremely helpful for detection, mapping the extent and resolution of the disease. It can identify cases, enables early institution of antituberculous chemotherapy and might obviate the need for surgery.

Synaptic plasticity in sympathetic ganglia from acquired and inherited forms of ouabain-dependent hypertension.

Altered sympathetic nervous system activity has been implicated often in hypertension. We examined short-term potentiation [posttetanic potentiation (PTP)] and long-term potentiation (LTP) in the isolated superior cervical ganglia (SCG) from Sprague-Dawley (SD) rats given vehicle, digoxin, or ouabain by subcutaneous implants as well as in animals with ouabain-induced hypertension (OHR), and inbred Baltimore ouabain-resistant (BOR) and Baltimore ouabain-sensitive (BOS) strains of rats. Postganglionic compound action potentials (CAP) were used to determine PTP and LTP following a tetanic stimulus (20 Hz, 20 s). Baseline CAP magnitude was greater in ganglia from OHR than in vehicle-treated SD rats before tetanus, but the decay time constant of PTP was significantly decreased in OHR and in rats infused with digoxin that were normotensive. In hypertensive BOS and OHR, the time constants for the decay of both PTP and LTP (t(L)) were increased and correlated with blood pressure (slope = 0.15 min/mmHg, r = 0.52, P < 0.047 and 6.7 min/mmHg, r = 0.906, P < 0.0001, respectively). In BOS and OHR, t(L) (minutes) was 492 +/- 40 (n = 7) and 539 +/- 41 (n = 5), respectively, and differed (P < 0.05) from BOR (257 +/- 48, n = 4), SD vehicle rats (240 +/- 18, n = 4), and captopril-treated OHR (370 +/- 52, n = 5). After the tetanus, the CAP at 90 min in BOS and OHR SCG declined less rapidly vs. SD vehicle rats or BOR. Captopril normalized blood pressure and t(L) in OHR. We conclude that the duration of ganglionic LTP and blood pressure are tightly linked in ouabain-dependent hypertension. Our results favor the possibility that enhanced duration of LTP in sympathetic neurons contributes to the increase in sympathetic nerve activity in ouabain-dependent hypertension and suggest that a captopril-sensitive step mediates the link of ouabain with LTP.

Persistent mullerian duct syndrome with teratoma in an ectopic testis: imaging features.

The persistent mullerian duct syndrome represents a rare form of male pseudohermaphroditism, secondary to mullerian inhibiting factor (MIF) deficiency. We describe imaging findings in a 30-year-old male (46 XY karyotype) with bilateral cryptorchidism and mullerian duct anomalies (presence of uterus and fallopian tubes). Grade-III teratoma with yolk sac tumour was detected in one of the undescended testis, lying in the pelvic cavity. The other testis was in the inguinal canal. The rest of the wolffian duct structures (e.g. prostate, seminal vesicles) were nearly normal. Very few reports of imaging findings of this entity have been published thus far, probably because of the rarity of entity, incidental detection of most of the cases at surgery and relatively asymptomatic clinical presentation.

Co-existing spinal cord and brain cavernous angiomas.

Cavernous angioma of spinal cord is an extremely rare vascular malformation. The association with brain cavernous angioma is even uncommon. There should be a high index of suspicion for a spinal cord lesion whenever a brain cavernous angioma is diagnosed, in cases with appropriate suggestive spinal symptoms. We present a case of cavernous angioma of the brain involving the genu of the corpus callosum, co-existing with spinal cord hemangioma. Involvement of the corpus callosum by a cavernous angioma is also uncommon. Intraventricular extension of this lesion was also detected.

Multimodality imaging for improved detection of epileptogenic foci in tuberous sclerosis complex.

OBJECTIVE: Using interictal alpha-[11C]methyl-l-tryptophan ([11C]AMT) PET scan, the authors have undertaken a quantitative analysis of all tubers visible on MRI or 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) PET, to determine the relationship between [11C]AMT uptake and epileptic activity on EEG. BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder, often associated with cortical tubers and intractable epilepsy. The authors have shown previously that [11C]AMT PET scans show high tracer uptake in some epileptogenic tubers and low uptake in the remaining tubers. METHODS: Eighteen children, age 7 months to 16 years, were studied. Patients underwent video-EEG monitoring, PET scans of [11C]AMT and [18F]FDG, and T2-weighted or fluid-attenuated inversion recovery (FLAIR) MRI. [11C]AMT uptake values were measured in 258 cortical tubers delineated with coregistered MRI or [18F]FDG scans. Uptake ratios were calculated between the [11C]AMT uptake in tubers and those for normal cortex (tuber/normal cortex). Using the region of epileptiform activity, the authors performed receiver operator characteristics (ROC) analysis and determined the optimal uptake ratio for detecting presumed epileptogenic tubers. RESULTS: Tuber uptake ratios ranged from 0.6 to 2.0. Tuber uptake ratios in the epileptic lobes were higher than those in the nonepileptic lobes (p < 0.0001). All 15 patients with focal seizure activity showed one or more lesions with uptake ratio above 0.98 in the epileptic lobe. ROC analysis showed that a tuber uptake ratio of 0.98 resulted in a specificity of 0.91. CONCLUSIONS: Cortical tubers with [11C]AMT uptake greater than or equal to normal cortex are significantly related to epileptiform activity in that lobe. Together, interictal [11C]AMT PET and FLAIR MRI improve the detection of potentially epileptogenic tubers in patients with TSC being evaluated for epilepsy surgery.

Extensive gliomas of visual tract in a patient of neurofibromatosis-I.

Although bilateral optic nerve gliomas are commonly found in patients with neurofibromatosis I, extensive gliomas involving the entire visual tracts, bilaterally are relatively rare. Usually the optic radiations are spared. We report a case of a 2-year-old child with extensive disease of bilateral visual pathways with involvement of the hypothalamus manifesting as obesity.

Effects of angiotensin II on sodium potassium pumps, endogenous ouabain, and aldosterone in bovine zona glomerulosa cells.

Angiotensin (Ang) II stimulates secretions of aldosterone and an endogenous ouabain-like steroid (EO) from bovine adrenal zona glomerulosa (BAG) cells. The BAG cell sodium pump, a possible target of EO, affects aldosterone secretion although little is known about this pump. Here, we describe the effects of Ang II on the characteristics of this transporter and steroid secretions. Under serum-free conditions, 3H-ouabain bound to a single class of sites on BAG cells. Binding of label was time and concentration dependent, was sensitive to extracellular potassium ions, and was displaced by ouabain and digoxin with EC50 of approximately 218 and approximately 232 nmol/L, respectively. Sodium pump-mediated 86Rb uptake was inhibited by ouabain (EC50 approximately 301 nmol/L). Ang II dose dependently augmented secretions of EO and aldosterone, increased ouabain-sensitive 86Rb uptake and 3H-ouabain binding, and increased the affinity for 3H-ouabain binding (Kd, from 205 to 80 nmol/L) with no change in the maximal number of sodium pumps (5.45x10(6)) per cell. Losartan blocked all effects of Ang II except EO secretion, which was inhibited by PD123319. We conclude that BAG cells express sodium pumps in high density and bind ouabain to a single class of low-affinity sites. The characteristics of the sodium pumps protect BAG cells from EO autotoxicity but may exclude them from mediating feedback inhibition of EO secretion. The effects of Ang II on sodium pump activity, ouabain binding affinity, and aldosterone secretion are mediated via Ang II type 1 receptors, whereas Ang II type 2 receptors augment EO secretion. The role of the Ang II-mediated increase in the ouabain sensitivity of BAG cell sodium pumps in the secretions of aldosterone and EO remains to be elucidated.

Imaging epileptogenic tubers in children with tuberous sclerosis complex using alpha-[11C]methyl-L-tryptophan positron emission tomography.

Several reports have indicated that cortical resection is effective in alleviating intractable epilepsy in children with tuberous sclerosis complex (TSC). Because of the multitude of cortical lesions, however, identifying the epileptogenic tuber(s) is difficult and often requires invasive intracranial electroencephalographic (EEG) monitoring. As increased concentrations of serotonin and serotonin-immunoreactive processes have been reported in resected human epileptic cortex, we used alpha-[11C]methyl-L-tryptophan ([11C]AMT) positron emission tomography (PET) to test the hypothesis that serotonin synthesis is increased interictally in epileptogenic tubers in patients with TSC. Nine children with TSC and epilepsy, aged 1 to 9 years (mean, 4 years 1 month), were studied. All children underwent scalp video-EEG monitoring, PET scans of glucose metabolism and serotonin synthesis, and EEG monitoring during both PET studies. [11C]AMT scans were coregistered with magnetic resonance imaging and with glucose metabolism scans. Whereas glucose metabolism PET showed multifocal cortical hypometabolism corresponding to the locations of tubers in all 9 children, [11C]AMT uptake was increased in one tuber (n=3), two tubers (n=3), three tubers (n=1), and four tubers (n=1) in 8 of the 9 children. All other tubers showed decreased [11C]AMT uptake. Ictal EEG data available in 8 children showed seizure onset corresponding to foci of increased [11C]AMT uptake in 4 children (including 2 with intracranial EEG recordings). In 2 children, ictal EEG was nonlocalizing, and in 1 child there was discordance between the region of increased [11C]AMT uptake and the region of ictal onset on EEG. The only child whose [11C]AMT scan showed no regions of increased uptake had a left frontal seizure focus on EEG; however, at the time of his [11C]AMT PET scan, his seizures had come under control. [11C]AMT PET may be a powerful tool in differentiating between epileptogenic and nonepileptogenic tubers in patients with TSC.

Observations on the nature, biosynthesis, secretion and significance of endogenous ouabain.

The human circulation contains four readily distinguishable biologically active inhibitors of the sodium pump that appear to be endogenous to mammals. Of these, one has been purified to homogeneity and by numerous chromatographic, mass spectral, biochemical, and physiological analyses has been shown to be a novel steroidal isomer of ouabain in which the location and orientation of two or more steroidal hydroxyl groups differ. The human endogenous "ouabain" (EO) is a high affinity reversible inhibitor of the pump with inotropic and vasopressor activity. Circulating levels of EO depend upon the adrenal cortex and metabolic events preceding and following pregnenolone formation are involved in EO biosynthesis. Within the adrenal gland, the stimulus-secretion mechanisms for EO secretion are distinct from those for aldosterone highlighting different regulation. Among Caucasians with essential hypertension, 30-45% have elevated circulating levels of EO. Sustained elevation of plasma ouabain in rats induces chronic hypertension with characteristics similar to those in patients and whose severity is determined by inherited factors and renal function. In conclusion, at least one of the mammalian counterparts to the cardiac glycosides is a novel steroidal isomer of ouabain. The isomer is secreted by the adrenal cortex, and augments cardiovascular function. The observation of this entity in the human circulation, the demonstration of its biosynthesis, and the existence of specific receptors suggest to us that EO is a novel adrenocortical hormone and may be part of a broader family of novel mammalian steroids that regulate the sodium pump and other processes.

Different signaling pathways mediate stimulated secretions of endogenous ouabain and aldosterone from bovine adrenocortical cells.

Angiotensin II stimulates secretion of corticosteroids and an ouabain-like compound from adrenocortical cells. The angiotensin AT1 and AT2 receptor subtypes have been linked with stimulated secretion of aldosterone and endogenous ouabain, respectively, but the second messenger mechanisms involved in the latter secretion are not known. Accordingly, we investigated the effects of several pharmacological agents that affect signaling pathways on the basal and stimulated secretions of aldosterone and endogenous ouabain from primary cell cultures of bovine adrenocortical cells. The AT2 receptor antagonist, PD 123319, blocked the effects of angiotensin II on secretion of endogenous ouabain but not aldosterone. Treatment of the cells with either dibutyryl cAMP, a membrane permeant analog, or the phorbol ester tetradecanoyl phorbol acetate stimulated aldosterone secretion but had no effect on the secretion of endogenous ouabain. On the other hand, the membrane permeant analog, 8BcGMP, maximally activated secretion of endogenous ouabain whereas incubation of cells with sodium orthovanadate blocked angiotensin II stimulated secretion of endogenous ouabain. Neither 8BcGMP nor sodium orthovanadate affected the basal or stimulated components of aldosterone secretion. These results show that the secretions of aldosterone and endogenous ouabain from bovine adrenocortical cells are mediated by different intracellular signaling mechanisms and provide evidence that the adrenal secretions of these steroids are regulated differently.