Cardiac Echinococcus Infection (Hydatid Pericarditis): Symptoms, Diagnosis and Treatment

Cardiac Echinococcus Infection (Hydatid Pericarditis): Symptoms, Diagnosis and Treatment

pediagenosis    July 04, 2026    Comment   

Echinococcus Infection and Hydatid Pericarditis

Cardiac Echinococcus Infection

Even in endemic regions, the heart is rarely affected by Echinococcus disease; the incidence of primary myocardial involvement is less than 2% in human echinococciasis (echinococcosis). The parasitic six-hooked embryo reaches the myocardium through the coronary circulation, having passed through the gastric or intestinal mucosa into the portal circulation, and through both the hepatic and the pulmonary capillary bed. It can establish itself and develop into an echinococcus cyst in almost any part of the myocardium, but cysts are mostly located in the walls of the ventricles (see Plate 6-149). There is a higher incidence of cysts in the myocardium of the left ventricle because its vascular bed is more abundant. The developing parasitic membranous cyst is surrounded by a fibrous sac or capsule, the adventitia. When it grows larger, the cyst may protrude into a cardiac cavity, the pericardial sac, or both, its greater and more prominent part usually projecting toward the pericardium.

Tremor: Causes, Symptoms, Types, Diagnosis & Treatment Explained

Tremor: Causes, Symptoms, Types, Diagnosis & Treatment Explained

pediagenosis    July 04, 2026    Comment   

Basal Ganglia and Movement Disorders

Tremor

Tremor is a rhythmic, oscillatory, involuntary movement caused by the alternating activation of agonist and antagonist muscles. The etiology of tremor is diverse and includes hereditary (familial tremor), degenerative (Parkinson disease), metabolic (thyroid, parathyroid, or hepatic disorders and hypoglycemia), toxins (nicotine, mercury, lead, carbon monoxide, manganese, arsenic, toluene), illicit drug use or medication-induced (neuroleptics, tricyclics, lithium, cocaine, alcohol, adrenaline, bronchodilators,  theophylline,  caffeine,  steroids,  valproate, amiodarone, thyroid hormones, vincristine), peripheral neuropathies (Charcot­ Marie ­Tooth disease, RoussyLevy syndrome, complex regional pain syndrome), and psychogenic disorders.

Diabetic Ketoacidosis (DKA) in Children: Symptoms, Causes, Diagnosis & Emergency Treatment

Diabetic Ketoacidosis (DKA) in Children: Symptoms, Causes, Diagnosis & Emergency Treatment

pediagenosis    July 04, 2026    Comment   

Figure 4-1 Insulin action

Diabetic Ketoacidosis

Diabetes is a chronic disease defined by hyperglycemia caused by insulin deficiency. (Chapter 71 provides a detailed discussion of diabetes mellitus.). This may be the result of a lack of insulin production, as in type 1 diabetes mellitus (T1DM) or the body’s ineffective use of the insulin it produces, as in type 2 diabetes mellitus. The most common form of diabetes in children is T1DM.

Ehlers-Danlos Syndrome (EDS): Symptoms, Causes, Types, Diagnosis & Treatment

Ehlers-Danlos Syndrome (EDS): Symptoms, Causes, Types, Diagnosis & Treatment

pediagenosis    July 04, 2026    Comment   

Genodermatoses and Syndromes

EHLERS-DANLOS SYNDROME

Ehlers-Danlos syndrome is a heterogeneous disease of defective connective tissue production. There are many subtypes, most caused by defects in collagen formation or in the posttranslational modification of collagen. This grouping of diseases has been confusing because of the variable nature of the subtypes and the lack of a universally adopted classification system. Under the most recent system, there are 7 distinct subtypes; under the historical classification, there were 11 types. The new classification system has not been universally adopted, which contributes to the confusion. As the genetic defects behind each subtype are determined, researchers and clinicians will gain a better understanding of the syndrome.

Neurofibromatosis (NF1 & NF2): Symptoms, Causes, Diagnosis, Treatment, and Long-Term Management

Neurofibromatosis (NF1 & NF2): Symptoms, Causes, Diagnosis, Treatment, and Long-Term Management

pediagenosis    July 02, 2026    Comment   

Neurofibroma

Neurofibromas are uncommon benign skin tumors that can be solitary but are more commonly found in multiples in patients with neurofibromatosis. Neurofibromatosis is one of the more common genodermatoses, afflicting 1 in every 3000 to 4000 individuals. It is caused by a defective tumor suppressor gene.

Tuberous Sclerosis (Bourneville Syndrome): Symptoms, Causes, Diagnosis, Treatment & Skin Signs

Tuberous Sclerosis (Bourneville Syndrome): Symptoms, Causes, Diagnosis, Treatment & Skin Signs

pediagenosis    July 02, 2026    Comment   

Genodermatoses and Syndromes

Tuberous sclerosis (Bourneville’s syndrome) is a multisystem disease that often manifests with cutaneous findings. It is inherited in an autosomal dominant manner and is directly caused by a defect in one of two genes, TSC1 or TSC2, usually due to a spontaneous mutation. TSC1 has been shown to encode the hamartin protein, whereas TSC2 gene encodes the tuberin protein. The skin, central nervous system (CNS), cardiovascular, respiratory, visual, and musculoskeletal systems are affected. This genodermatosis has an extremely variable phenotype. At one extreme is the severely disabled and mentally delayed individual with severe seizure disorders; at the other end of the spectrum is the individual with mild skin disease and unappreciable CNS disease.

Tics and Tourette Syndrome: Causes, Symptoms, Diagnosis, and Treatment Guide

Tics and Tourette Syndrome: Causes, Symptoms, Diagnosis, and Treatment Guide

pediagenosis    July 02, 2026    Comment   

Tics and Tourette Syndrome

Tics are sudden, rapid, stereotyped, repetitive, non­rhythmic movements or vocalizations affecting discrete muscle groups. Most experts agree and clinical experience dictates that tics are preceded by a sensory component, described by patients as an “urge.” When patients are asked to prevent movements from occurring, an uncomfortable inner sensation builds and an urge to “release” develops, resulting in expression of the tics.

The spectrum of tics includes transient tics of childhood when present for less than 1 year, chronic motor or vocal tics when tics are present for more than 12 months, and Tourette syndrome, defined by the presence of both motor and vocal tics for more than 12 months.

Tics may be classified according to complexity of symptoms as simple motor or vocal tics when involving only a few muscles or simple sounds, such as eye blinking, shoulder shrugging, facial grimacing, whistling, grunting, throat clearing, snorting, chirping, or sniffing. Many such youngsters are initially mistakenly diagnosed as having chronic rhinitis or “allergies,” or punished unnecessarily for loud behaviors. Once considered rare, schoolteachers now easily identify tics and may be the first to call attention to a child’s unique behavior. In complex motor or vocal tics, multiple muscle groups are recruited in orchestrated bouts of involuntary movements or utterances of words and sentences or phrases. Examples include hand gestures, jumping, touching, pressing, shouting words, or speech blocking. Some individuals may exhibit copropraxia, the sudden performance of obscene gestures or echopraxia, the involuntary spontaneous imitation of someone else’s movements.

Tourette syndrome (TS) is characterized by multiple motor and vocal tics. In many TS patients, obsessive­compulsive behaviors and attention deficit disorder, or both, may be present. Anxiety, depression, and self­ injury behaviors may complicate the clinical picture.

Tics may be primary or “idiopathic” or secondary, in which a definable cause is found. Primary tics are by far the more common in children and adolescents, with secondary disorders in that age group being rare. In adults, trauma, encephalitis, stroke, carbon monoxide poisoning, neurosyphilis, Creutzfeldt­Jakob disease, and central nervous system (CNS) injury from hypoglycemia may result in tics or Tourettism. Some genetics disorders in which tics have been described include Huntington disease, neuroacanthocytosis, neuroferri­tinopathy (Hallervorden­Spatz disease), dystonia with tics, tuberous sclerosis complex, and some cases of Duchenne muscular dystrophy. A few patients with Down syndrome, Asperger/autism spectrum, and fragile X­tremor syndrome have also been reportedto have tics. The use of illicit drugs or medications may result in tics, Tourettism, or punding, particularly the use of cocaine, amphetamines, and antiepileptic medications (phenobarbital, phenytoin, and carbamazepine). Less commonly, opioids, lithium, levodopa, and antidepressants may induce or worsen tics.

The substrate for tics and Tourette syndrome seems to reside in the basal ganglia and related structures. Supporting evidence for this concept includes the clinical observation of tic improvement when patients are treated with dopamine­blocking or dopamine­depleting agents. Other evidence comes from func­ tional imaging studies demonstrating volumetric striatal changes and, in some, increased dopamine synaptic content. Recently, deep brain stimulation has side effects. Tetrabenazine, a dopamine depletor, may be useful in some cases. A stimulant such as methylphenidate does not worsen tics as previously thought. It can therefore be safely used in those with tics and attention deficit disorder. The serotonin reuptake inhibitors are helpful in treating anxiety, depression, or obsessive­compulsive disorder in patients with tics or Tourette syndrome. Botulinum toxin therapy has proven to be of some value when used in patients with dystonic tics. A behavioral therapeutic approach using habit reversal therapy at its core has been shown to be effective in a recent large multicenter study. Thalamic or pallidal deep brain stimulation is a promising strategy in refractory cases.

Myoclonus: Causes, Symptoms, Diagnosis, Types, Postanoxic Myoclonus & Treatment Guide

Myoclonus: Causes, Symptoms, Diagnosis, Types, Postanoxic Myoclonus & Treatment Guide

pediagenosis    July 02, 2026    Comment   

 Myoclonus

Basal Ganglia and Movement Disorders

Myoclonus is a brief, shocklike muscle jerk, which may be classified according to origin, (cortical, subcortical, brainstem, and spinal myoclonus) and distribution (focal, segmental, multifocal, or generalized). Cortical myoclonus may be epileptic (as in Baltic myoclonus or progressive myoclonic epilepsy, photosensitive myoclonus, epilepsia partialis continua) or part of a neurodegenerative disorder (corticobasal degeneration, Alzheimer dementia, diffuse Lewy body disease, and others). Myoclonus can be classified according to  etiology as idiopathic/genetic (familial myoclonus, myoclonus­dystonia), physiologic (hypnic jerks or diaphragmatic myoclonus/hiccups) or secondary/symptomatic when a cause for the myoclonus is clearly identified. Examples of the latter group may include encephalitis, hypoxia, toxins, storage diseases, and basal ganglia degenerations, as in Huntington disease, Wilson disease, and certain other disorders). Myoclonus may be positive due to a brief muscle contraction or negative when muscle tone is briefly lost, as in asterixis.

Anoxic brain injuries may result in myoclonus, which, in turn, may be cortical, diencephalic, or reticular in origin; stimulus sensitive or action induced; and segmental, generalized, or multifocal in distribution. This type of myoclonus may be focal, preferentially affecting the distal limb muscles, or multifocal with spontaneous, reflexive or stimulus­sensitive jerks accentuated by movement. Frequently, anoxic­induced myoclonus is accompanied by secondary seizures, particularly after cardiopulmonary arrest. Status epilepticus is found in 32% of postanoxic patients, and in many, multifocal myoclonus alone or in combination with generalized tonic­clonic seizures is frequently observed. The incidence of myoclonic seizures is bimodal, with the majority of them occurring within 12 hours after cardiopulmonary resuscitation and the remaining occurring several days later. Electroencephalography (EEG) is useful when evaluating these patients, particularly when status epilepticus is suspected. The most frequent EEG findings include diffuse slowing with or without spike or polyspike complexes that are sometimes time locked to the myoclonic jerks. A burst­suppression EEG pattern, when recorded, has a poor prognostic significance. Magnetic resonance imaging of the brain may show diffusion restriction in the cortical and subcortical gray matter between 24 hours and 13 days. Isolated myoclonus generally does not require treatment unless it interferes with mechanical ventilation or nursing care. Myoclonus status is refractory to treatment, may require multiple antiepileptic drugs, and, when accompanied by convul­ sive status epilepticus, is best controlled with deep anesthesia.

Electrophysiologically, myoclonus is characterized by a muscle bursts that are less than 75 msec in duration. When the cerebral cortex is affected, a “giant” somatosensory evoked cortical response time locked to the onset of the jerk in back­averaged EEG may be obtained.

 

POSTANOXIC MYOCLONUS

In 1963, James Lance and Raymond D. Adams reported the first series of patients with the syndrome of intention or action myoclonus as a sequel to hypoxic encephalopathy. In postanoxic myoclonus, axial and proximal muscle groups are particularly affected, the myoclonus often occurring when patients perform an action, such as standing or reaching for an object (action myoclonus). Limb and truncal ataxia, cerebellar outflow tremor, and dysarthria are other common accompaniments. The exact substrate of postanoxic myoclonus generation is not clear. Postanoxic myoclonus may be the result of cortical or subcortical injury or be due to alterations in brainstem serotonergic pathways. The serotonergic raphe nuclei have frequently been implicated.

Some forms of myoclonus, particularly those of subcortical origin, are believed to arise from the reticular system primarily from the nucleus reticularis gigantocellularis. This reticular reflex myoclonus is characterized by a brief electromyographic burst lasting 10 to 30 msec, with generalized bilateral synchronous activation of muscles following a distribution suggesting spread up the brainstem and down to the cord.

Essential myoclonus may be idiopathic or familial, beginning in the first to second decade of life. In patients with essential myoclonus, the neurologic examination fails to demonstrate other deficits. In a few families, lower verbal scores have been reported and occasionally mental retardation. Similar to essential tremor, alcohol may help to ameliorate the symptoms, but the incidence of alcoholism is increased. In patients with myoclonus-dystonia, there is an autosomal pattern of inheritance, men are more affected than women, and there is a higher incidence of alcoholism and behavioral disturbances.

Wilson Disease (Hepatolenticular Degeneration): Symptoms, Causes, Diagnosis, MRI Findings, and Treatment Guide

Wilson Disease (Hepatolenticular Degeneration): Symptoms, Causes, Diagnosis, MRI Findings, and Treatment Guide

pediagenosis    July 02, 2026    Comment   

Also known as hepatolenticular degeneration, Wilson disease is an autosomal recessive disorder that occurs in 1 of 30,000 individuals. The abnormal gene, the ATP7B (adenosine triphosphate) gene, is located on chromosome 13. The defective protein, adenosine triphosphatase (ATPase), is involved in the transport and incorporation of copper into ceruloplasmin and the vesicular compartment near the canalicular membrane for further bile excretion.

Esophagoscopy and Endoscopic Ultrasound (EUS): Advanced Technology for Early Detection of Esophageal Cancer

Esophagoscopy and Endoscopic Ultrasound (EUS): Advanced Technology for Early Detection of Esophageal Cancer

pediagenosis    June 13, 2026   

Esophagoscopy and Endoscopic Ultrasound

The ability of being able to introduce a flexible instrument with a charge­coupled device safely into the gastrointestinal tract has revolutionized the practice of gastroenterology. Endoscopic examination of the esophagus shows extensive detail of the mucosal lining, some imaging of abnormalities that lead to intramural or extramural indentation or compression of the lumen, respectively, and esophageal motility abnormalities as estimated by sphincter tone and esophageal diameter. Mucosal abnormalities seen are best characterized as inflammatory or neoplastic. Inflammatory lesions may vary in intensity from mild superficial erythema to frank ulceration with complete destruction of the mucosa.