Hemorrhoids: what they are, symptoms and causes


  • What are hemorrhoids?
  • Hemorrhoidal disease
  • Stages of Hemorrhoids
  • Hemorrhoids symptoms
  • What causes hemorrhoids

What are hemorrhoids?

Hemorrhoids, also called piles, are part of the normal anatomical structure found in us all from birth. Hemorrhoids are located around the anus (external hemorrhoids) and in the anal canal (internal hemorrhoids).

Hemorrhoidal cushions contain a dense network of blood vessels and, by engorging, form a plug in the anal canal, thus contributing to fecal continence.

Hemorrhoids can be internal or external:

  • Internal hemorrhoids
    Internal hemorrhoids are the hemorrhoids in the anal canal above the “pectinate line”, also known as the “pain line” because below this area you feel pain. Thus, you do not normally see or feel these hemorrhoids until they become swollen and start to bleed.
  • External hemorrhoids
    These are hemorrhoidal cushions located outside the anus below the pain line and covered by anoderm, a very sensitive layer of skin. Sometimes blood clots (thrombus) can form inside external hemorrhoids and cause severe pain and swelling.

Hemorrhoidal disease

Hemorrhoidal disease is one of the most widespread anorectal disorders in Western countries.

Hemorrhoidal disease main symptoms are:

  • Bleeding: hemorrhoidal cushions become bruised and start to bleed.
  • Hemorrhoidal prolapse: hemorrhoidal cushions excessively increase in size and become misaligned.
  • Hemorrhoidal thrombosis: painful blood clots form inside hemorrhoidal cushions.

Hemorrhoids can be classified as grade I, II, III and IV, depending on the severity of the symptoms, mainly prolapse.


Stages of hemorrhoids

The classification of hemorrhoids is based on the symptoms observed during clinical examination, and it is extremely important for choosing the most suitable treatment.

GRADE I: hemorrhoids are visible on anoscopy and may bulge out on straining, despite not being prolapsed.

GRADE II: prolapse is visible at the anal margin when straining and shrinks spontaneously afterwards.

GRADE III: persistent prolapse of the mucous membrane outside of the anal canal which may be pressed in by hand.

GRADE IV: permanent prolapse of the external mucous membrane of the anal canal that cannot be pressed in.

Note: In all grades above, arterial bleeding is often associated.


Hemorrhoids symptoms

The most common symptoms of hemorrhoid disease are bleeding, pain, itching around the anus and prolapse.

  • Bleeding
    In hemorrhoidal disease, hemorrhoidal cushions are more sensitive to trauma and therefore there is a higher risk of hemorrhoidal bleeding. Bleeding hemorrhoids are one of the main symptoms of the disease, along with pain and itching.
    Hemorrhoidal bleeding is one of the most alarming symptoms for those suffering with hemorrhoids. In less severe cases, bright red blood found on toilet paper or feces is light or rare. On the other hand, in advanced grade hemorrhoids, bleeding of the prolapsed hemorrhoid tissue may be constant. Blood loss is especially common with internal hemorrhoids.
    Don’t assume rectal bleeding is only a symptom of hemorrhoids. Anorectal bleeding can be associated with other diseases, like colorectal and anal cancer.
  • Pain
    Along with bleeding, another common symptom is pain, both in the case of internal and external hemorrhoids. Normally, internal hemorrhoids are associated with pain only when the volume of the cushion increases enough to cause significant bulging out of the anus. In these cases, you may notice pain or increased pain at the time of defecation.
  • Anal itching
    While rectal pain is a more frequent symptom of external hemorrhoids, the itching sensation and discomfort around the anus is linked with internal hemorrhoids. Internal hemorrhoids tend to secrete mucous that causes irritation and itching around the anus.
  • Prolapse
    Increase in volume of one or more hemorrhoidal cushions causes the hemorrhoids to slide into the anal canal and to bulge out during defecation, causing hemorrhoidal prolapse.

The prolapse may shrink back on its own, need manual shrinking or be irreducible, depending on the severity of the disease. The treatment choice largely depends on the extent of the prolapse and on the severity of the other symptoms.
For this reason, the assessment of the prolapse must be precise and carried out both at rest and during straining for defecation. It is thus important to see a doctor and undergo a colorectal exam when symptoms first appear.


What causes hemorrhoids

Vascular theory and mechanical theory are amongst the most accredited explanations of the causes of hemorrhoid disease.

  • Vascular theory
    The vascular theory considers hemorrhoids swelling as caused by an alteration in the arteriovenous blood flow. Under the pressure of excessive blood flow, the hemorrhoidal cushions stretch and swell. The increase in arterial in-flow and the reduction in venous out-flow leads to bulging of hemorrhoids and in severe cases, to hemorrhoidal prolapse outside the anus. Increased pressure in the anorectal area can be due to different factors like straining during defecation, low-fiber diet or sitting too long on the toilet.
  • Mechanical theory
    The mechanical theory attributes the prolapse of hemorrhoids to the progressive weakening of the tissue that surrounds the hemorrhoidal cushions.
    One of the causes of the weakening of tissues is age. With age, the tissues supporting the cushions in the anorectal area become more fragile and stretch and the risk of prolapsing hemorrhoids is higher. This can also happen during pregnancy when the baby’s weight increases the pressure on the anorectal region.
  • Other risk factors
    There then are other factors that may contribute to the development of hemorrhoidal disease, in particular:
    • family history
    • obesity
    • environmental factors (e.g., diet, sedentary lifestyle)
    • chronic constipation or diarrhea