Vascular Dementia: Causes, Symptoms, Diagnosis and Treatment

Vascular Dementia: Causes, Symptoms, Diagnosis and Treatment

pediagenosis    October 21, 2026    Comment   

VASCULAR DEMENTIA

Vascular dementia is interesting in that many of those who do have a true vascular dementia are not diagnosed with it, while many who probably do not have a vascular dementia are diagnosed with it. The most straightfor-ward presentations are those in which an individual with normal cognition has a large stroke that causes a combination of cognitive signs, such as aphasia and a memory retrieval problem. If the patient cannot resume their prestroke day-to-day level of function because of these new cognitive deficits, the criteria for vascular dementia are met, but because the stroke so clearly caused the deficits, they are held to simply represent the consequences of a stroke (as opposed to a frank vascular dementia). On the other hand, some patients will present with a gradually progressive dementia, a retention-type memory deficit, no motor signs, no history of sensory or motor changes, and a neuroimaging study that shows subcortical changes that could be consistent with “small vessel cerebrovascular disease.” In the elderly, such patients almost always have the plaques and tangles that are expected in Alzheimer disease. In such cases, despite the neuroimaging changes, it is probably more appropriate to consider Alzheimer disease as the primary etiology. Still, the frequent association between Alzheimer disease and cerebrovascular pathology suggests these conditions may be linked in some way.

Treatable Dementias: Reversible Causes, Symptoms & Treatment

Treatable Dementias: Reversible Causes, Symptoms & Treatment

pediagenosis    October 21, 2026    Comment   

TREATABLE DEMENTIAS

Although in some ways cognitive performance abilities evolve throughout adulthood, many elderly people remain mentally sharp into their ninth and tenth decades. The emergence of uncharacteristic changes in an individual’s cognition that impacts their usual activities should, therefore, trigger an evaluation for possible etiologies.

Trichinosis: Symptoms, Diagnosis & Heart Complications

Trichinosis: Symptoms, Diagnosis & Heart Complications

pediagenosis    October 20, 2026    Comment   

TRICHINOSIS

Parasitic Heart Disease

Trichinosis

Trichinosis is caused by the roundworm Trichinella spiralis. When raw or incompletely cooked pork or a pork product containing living trichina larvae is eaten, the walls of the cysts are digested, liberating the microscopic larvae. Within the small intestine of the host, the freed larvae maturate during the next 2 days to adult male or female worms, and copulate. Beginning 5 days after ingestion of the infected meat and, in humans, continuing for as long as 12 weeks, the gravid adult female worms, which are partially embedded in the mucosal wall of the small bowel, give birth to larvae. The latter successively enter the lacteals of the intestinal villi, right ventricular cavity, pulmonary capillaries, and systemic circulation. By predilection the larvae penetrate skeletal muscle fibers, where they enlarge progressively, simultaneously causing degeneration of the fibers and provoking a local reaction characterized by edema, hyperemia, and granulomatous and eosinophilic inflammation. Approximately 30 days after invasion of the muscle fibers, the larvae, which now have assumed a characteristic coiled appearance, attain their maximal size and become encapsulated. In nature, the life cycle of the parasite is completed when a carnivorous mammal becomes infected with the parasite, as the result of ingesting the flesh of another animal containing living larvae (see Plate 6-146).

Scrotal Skin Diseases: Causes, Symptoms, Diagnosis, and Treatment

Scrotal Skin Diseases: Causes, Symptoms, Diagnosis, and Treatment

pediagenosis    October 15, 2026   

SCROTAL SKIN DISEASES I: CHEMICAL AND INFECTIOUS

Many skin diseases of infectious, allergic, or metabolic origin can involve the scrotum. Among many yeasts, molds, and fungi, only a few are infectious and are termed dermatophytes (“skin fungi”). Skin fungi live only on the dead layer of keratin protein on the skin surface. They rarely invade deeper and cannot live on mucous membranes. Infections by the fungus tinea cruris (ring-worm) are very common in the groin and scrotum. It involves desquamation of the scrotal skin and contiguous surfaces of the inner thighs and itches (“jock itch”). Tinea begins with fused, superficial, reddish-brown, well-defined scaly patches, which extend and coalesce into large, symmetrical, inflamed areas. The margins of the lesions are characteristically distinct. The initial lesion may become macerated and infected and is painful and itches. Sweating, tight clothing or obesity favor development and recurrence of this fungal infection, derived mainly from the genera Trichophyton and Microsporum. These same organisms cause tinea pedis or “athlete’s foot.”

Direct and Indirect Inguinal Hernias : Causes, Symptoms & Treatment

Direct and Indirect Inguinal Hernias : Causes, Symptoms & Treatment

pediagenosis    October 15, 2026    Comment   

INDIRECT AND DIRECT INGUINAL HERNIAS

Hernia (a word derived from the Greek, meaning “sprouting forth”) has been defined, from the time of A. Cornelius Celsus (second century AD), as a protrusion of an organ or tissue, through an abnormal opening, from the organ’s natural place in a cavity. Hernias are classified by the cause or the anatomic location of the defect.

Basal Cell Nevus Syndrome (Gorlin Syndrome): Symptoms & Treatment

Basal Cell Nevus Syndrome (Gorlin Syndrome): Symptoms & Treatment

pediagenosis    October 14, 2026    Comment   

MANIFESTATIONS OF BASAL CELL NEVUS SYNDROME

BASAL CELL NEVUS SYNDROME

Basal cell nevus syndrome (BCNS), also known as nevoid basal cell carcinoma syndrome or Gorlin syndrome, is an uncommon autosomal dominant genodermatosis caused by mutations in the patched-1 (PTCH1) gene on chromosome 9. Approximately 40% of cases represent new, spontaneous mutations. Affected individuals are predisposed to the development of multiple basal cell carcinomas (BCCs), often in the hundreds over their lifetime. The diagnosis of this syndrome is based on a number of established criteria.

Chagas Disease: Causes, Symptoms, Heart Damage & Complications

Chagas Disease: Causes, Symptoms, Heart Damage & Complications

pediagenosis    October 14, 2026    Comment   

CHAGAS DISEASE (TRYPANOSOMIASIS)

Chagas Disease

Chagas disease, also called South American (or American) trypanosomiasis, is a menace to millions of people in South-Central America. The parasite Trypanosoma cruzi enters the body, usually through the bite of a reduviid (assassin or kissing bug), or by the transfusion or inoculation of contaminated blood. The parasite circulates only in its trypanosomal form. It enters a body cell, transforms to a leishmania, and multiplies to form a leishmanial cyst, which ruptures the invaded cell. In this stage the parasites are released and transformed into trypanosomes, which circulate in the blood and invade other cells, thus continuing the cycle. The cardiac muscle cells are targeted in most cases, but with some strains in particular areas, there is equal or greater proclivity for the peripheral ganglion cells to be invaded or destroyed. In the rarer acute cases, all cells and tissues may be invaded, but in chronic cases, major damage is to the cardiac muscle cells and peripheral ganglion cells (see Plate 6-147).

Small Intestinal Bleeding: Causes, Symptoms, Diagnosis & Treatment

Small Intestinal Bleeding: Causes, Symptoms, Diagnosis & Treatment

pediagenosis    October 13, 2026    Comment   

VASCULAR MALFORMATION OF SMALL INTESTINE AND OTHER CAUSES OF SMALL INTESTINAL BLEEDING

Approximately 5% of cases of gastrointestinal bleeding occur in the small bowel, defined as the region between the ampulla of Vater and the ileocecal valve. Small intestinal vascular malformations are responsible for the majority of cases of small intestinal bleeding. They are more often seen in elderly patients, as is enteropathy induced by nonsteroidal antiinflammatory drugs (NSAIDs). Small intestinal tumors, Crohn disease, and nonspecific enteritis are more common in individuals under 40 years of age. Rarer causes include Meckel diverticulum, hemobilia, hemosuccus pancreaticus, and aortoenteric fistula.

Normal-Pressure Hydrocephalus: Symptoms, Causes, Diagnosis & Treatment

Normal-Pressure Hydrocephalus: Symptoms, Causes, Diagnosis & Treatment

pediagenosis    October 12, 2026    Comment   

NORMAL-PRESSURE HYDROCEPHALUS

The “plumbing system” of the central nervous system (CNS) operates in a delicate balance. Fluid produced in the choroid plexus of the lateral ventricles circulates through the third ventricle, cerebral aqueduct (of Sylvius), and fourth ventricle. After exiting from the roof of the fourth ventricle, the cerebrospinal fluid (CSF) circulates around the brain within the subarachnoid cisterns, and is ultimately absorbed by the arachnoid granulations into the circulation. If more CSF is produced than is absorbed, the ventricles and subarachnoid space distend with fluid. In the adult, this imbalance leads to enlargement of the ventricles, which then encroach on the normal cerebral white matter, especially frontally.

Amebic Pericarditis: Causes, Symptoms, Diagnosis & Treatment

Amebic Pericarditis: Causes, Symptoms, Diagnosis & Treatment

pediagenosis    October 11, 2026    Comment   

Amebic Pericarditis

Amebiasis

Amebiasis, transmitted by the protozoan Entamoeba histolytica, is considered initially and predominantly an intestinal disease, but it involves the liver in a substantial proportion of patients. The infective encysted form of the parasite, communicated person to person without an intermediate host and usually by water or food contaminated by human fecal material, enters the intestinal tract by the mouth, passes through the stomach, and loses its cystic wall in the small intestine. There the cyst, 5 to 20 µ in diameter, having matured during its passage, releases from one to four trophozoites (vegetative form), which in contrast to the cyst, are mobile but do not survive outside the host’s body. The amebas, which have attached themselves to the colonic wall, migrate into the crypts and penetrate the epithelium and muscularis. From the submucosa, the amebas move along to other organs, particularly the liver, creating there the chronic nonsuppurative form of amebic hepatitis or producing abscesses. Other trophozoites are excreted in the encysted form, thus maintaining the life cycle.