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General anasarca is extensive interstitial fluid accumulation, produced when vascular filtration exceeds the capacity of lymphatic drainage and the body's regulation of salt and water. Several mechanisms commonly act together.

Raised venous and capillary hydrostatic pressure promotes filtration. Heart failure, especially when systemic venous pressure is elevated, is a major example; renal retention of sodium and water reinforces the swelling. Severe kidney failure can itself cause general fluid overload when salt and water cannot be excreted adequately. Acute glomerulonephritis may therefore cause widespread oedema without requiring the extremely low plasma protein concentration of every nephrotic case.^[ref]

Reduced plasma oncotic pressure contributes when circulating albumin is markedly depleted. Causes include heavy urinary protein loss in nephrotic syndrome, reduced synthesis in advanced liver disease, protein loss through the intestine, and severe malnutrition. In cirrhosis, altered circulation and renal salt retention add to reduced protein synthesis; the mechanism cannot be reduced to a single blocked vein. Likewise, nephrotic syndrome can include primary renal salt retention as well as a fall in oncotic pressure.^[ref]

Increased vascular permeability during severe systemic inflammation, sepsis or extensive tissue injury can allow fluid and protein into the interstitium. Impaired lymphatic drainage can amplify systemic oedema, although a single obstructed lymphatic or vein ordinarily causes regional rather than general swelling. Excess administered fluid and some drugs can contribute by salt retention or altered vascular tone. Multiple mechanisms are particularly likely in a severely ill patient.

A nineteenth-century description would group much of this as cardiac, renal or hepatic “dropsy,” and might invoke an impoverished state of the blood. Modern physiology specifies the abnormalities that those broad descriptions leave unresolved. A general examination should distinguish pitting fluid accumulation from a predominantly non-pitting disorder such as myxoedema, and from isolated ascites. The distribution, jugular venous filling, heart and lung findings, urinary albumin, renal function and plasma albumin help distinguish causes. Anasarca is a sign with several possible causes, not a diagnosis of renal disease by itself.

Historical “amyloid disease” denotes the waxy or lardaceous visceral change, especially in the spleen, liver and kidneys; modern amyloidosis denotes deposition of misfolded protein fibrils. The old descriptive appearance and the modern chemical explanation must be kept distinct.

In nineteenth-century usage the affected organs could be enlarged, firm and unusually translucent or wax-like on section. The name amyloid means starch-like. The historical chemical argument relied on colour reactions with iodine and sulfuric acid, suggesting affinity with starch or cellulose. Such a reaction was a clue to recognition, not a modern identification of the deposited substance. Rudolf Virchow's 1856 account explicitly discusses the waxy change of the spleen, liver and kidneys, and its occurrence with longstanding destructive disease.^[ref]

The three principal visceral examples can be described more precisely:

The distribution is not confined to those three organs. Amyloidosis can also affect the gastrointestinal tract, heart, blood vessels and other sites; the pattern depends on the precursor protein. Modern examples include AA amyloidosis associated with sustained inflammation, AL amyloidosis involving immunoglobulin light chains, and transthyretin amyloidosis. This classification is a present-day explanation, not a list of molecular diagnoses asserted for unnamed 1867 patients.^[ref]

Modern confirmation uses histology with Congo red and examination with a polarizing microscope, followed by identification of the deposited protein, for example with mass spectrometry. The characteristic birefringence supports identification of amyloid; typing distinguishes biologically different diseases. These are later laboratory methods, not apparatus available to the candidate in 1867.^[ref]

Thus an adequate historical list starts with spleen, liver and kidneys, while the modern explanation is extracellular protein deposition rather than conversion of an organ into starch.

Vomiting is a coordinated nervous motor act that can be initiated from the digestive system, circulating emetic substances, the vestibular system, or higher and lower brain pathways. A cause need not lie in the stomach.

Local causes include irritant food or poisons, gastritis, gastroenteritis, gastric outlet obstruction and intestinal obstruction. Chemical irritation, inflammation or distension activates visceral sensory pathways, notably afferents of the vagus nerve, which relay to the medulla oblongata. In obstruction, retention and distension provide continuing stimulation; merely seeing food return does not imply excessive gastric contractile strength. Peritonitis and painful disease elsewhere in the abdomen can also recruit visceral afferent pathways.^[ref]

Circulating emetic agents, including some drugs and metabolic products accumulating in kidney failure, act partly through the area postrema, a chemosensitive region with unusually direct access to substances in the blood. Gastrointestinal and blood-borne inputs converge through the nucleus tractus solitarius and connected medullary networks. It is more accurate to describe interacting groups of neurons than one isolated “vomiting centre”.^[ref]

Other important groups are motion sickness, where information from the vestibular system conflicts with other sensory information; migraine and intracranial disease, including raised intracranial pressure from a brain tumour or intracranial haemorrhage; and higher-centre influences such as a repulsive sight, smell, fear or learned association. Pregnancy-associated vomiting belongs in the differential, with endocrine and central contributions rather than an explanation that it is simply mechanical pressure by the uterus upon the stomach. These causes engage different inputs to an overlapping final motor programme.^[ref]

The act itself requires several coordinated changes. The proximal stomach and lower oesophageal sphincter relax; retrograde activity can bring contents of the upper intestine into the stomach; the diaphragm and abdominal muscles generate a pressure gradient that expels the contents. During expulsion the upper passage opens while coordinated laryngeal closure helps protect the airway. Retching and actual expulsion are related stages, and neither should be confused with effortless regurgitation.^[ref]

This mechanism explains the diversity of causes: many sensory and chemical inputs can recruit the same coordinated output. A pressure recording and observation of gastrointestinal movements during an emetic response can distinguish the patterned act from a simple spontaneous return of contents; they would not, without further evidence, identify the original cause in an individual.

Reduction of renal function, which may affect the elimination and toxicity of medicines without amounting to complete kidney failure.