Hemorrhoids (US English) or haemorrhoids , are vascular structures in the anal canal which help with stool control. They become pathological or piles when swollen or inflamed. In their physiological state they act as a cushion composed of arterio-venous channels and connective tissue that aid the passage of stool. The symptoms of pathological hemorrhoids depend on the type present. Internal hemorrhoids usually present with painless rectal bleeding while external hemorrhoids present with pain in the area of the anus.
There are two types of hemorrhoids, external and internal, which are differentiated via their position with respect to the dentate line.
External hemorrhoids are those that occur outside the anal verge (the distal end of the anal canal). Specifically, they are varicosities of the veins draining the territory of the inferior rectal arteries, which are branches of the internal pudendal artery. They are sometimes painful, and often accompanied by swelling and irritation. Itching, although often thought to be a symptom of external hemorrhoids, is more commonly due to skin irritation. External hemorrhoids are prone to thrombosis: if the vein ruptures and/or a blood clot develops, the hemorrhoid becomes a thrombosed hemorrhoid.
Internal hemorrhoids are those that occur inside the rectum. Specifically, they are varicosities of veins draining the territory of branches of the superior rectal arteries. As this area lacks pain receptors, internal hemorrhoids are usually not painful and most people are not aware that they have them. Internal hemorrhoids, however, may bleed when irritated. Untreated internal hemorrhoids can lead to two severe forms of hemorrhoids: prolapsed and strangulated hemorrhoids. Prolapsed hemorrhoids are internal hemorrhoids that are so distended that they are pushed outside the anus. If the anal sphincter muscle goes into spasm and traps a prolapsed hemorrhoid outside the anal opening, the supply of blood is cut off, and the hemorrhoid becomes a strangulated hemorrhoid.
§ Grade I: No prolapse.
§ Grade II: Prolapse upon defecation but spontaneously reduce.
§ Grade III: Prolapse upon defecation and must be manually reduced.
§ Grade IV: Prolapsed and cannot be manually reduced.
Hemorrhoids usually are present with itching, rectal pain, or rectal bleeding. In most cases, symptoms will resolve within a few days. External hemorrhoids are painful, while internal hemorrhoids usually are not unless they become thrombosed or necrotic.
The most common symptom of internal hemorrhoids is bright red blood covering the stool, a condition known as hematochezia, on toilet paper, or in the toilet bowl. They may protrude through the anus. Symptoms of external hemorrhoids include painful swelling or lump around the anus.
A number of factors may lead to the formations of hemorrhoids including irregular bowel habits (constipation or diarrhea), exercise, nutrition (low-fiber diet), increased intra-abdominal pressure (prolonged straining), pregnancy, genetics, absence of valves within the hemorrhoidal veins, and aging.
Other factors that can increase the rectal vein pressure resulting in hemorrhoids include obesity and sitting for long periods of time.
During pregnancy, pressure from the fetus on the abdomen and hormonal changes cause the hemorrhoidal vessels to enlarge. Delivery also leads to increased intra-abdominal pressures. Surgical treatment is rarely needed, as symptoms usually resolve post delivery.
The best way to prevent hemorrhoids is to keep stools soft so they pass easily, thus decreasing pressure and straining, and to empty bowels as soon as possible after the urge occurs. Exercise, including walking, and increased fiber in the diet help reduce constipation and straining by producing stools that are softer and easier to pass. Spending less time attempting to defecate and avoiding reading while on the toilet have been recommended.
A visual examination of the anus and surrounding area may be able to diagnose external or prolapsed hemorrhoids. A rectal exam may be performed to detect possible rectal tumors, polyps, an enlarged prostate, or abscesses. This examination may not be possible without appropriate sedation due to pain, although most internal hemorrhoids are not present with pain.
Visual confirmation of internal hemorrhoids is via anoscopy or proctoscopy. This device is basically a hollow tube with a light attached at one end that allows one to see the internal hemorrhoids, as well as possible polyps in the rectum.
Conservative treatment typically consists of increasing dietary fiber, oral fluids to maintain hydration, non-steroidal anti-inflammatory drugs (NSAID)s, sitz baths, and rest. Increased fiber intake has been shown to improve outcomes, and may be achieved by dietary alterations or the consumption of fiber supplements.
While many topical agents and suppositories are available for the treatment of hemorrhoids, there is little evidence to support their use. Preparation H may improve local symptoms, but does not improve the underlying disorder, and long-term use is discouraged due to local irritation of the skin.