H. Pylori - Latest Discoveries And Treatment Options

Helicobacter Pylori aka H. Pylori

Helicobacter pylorus (H. pylori) is a bacterium from the family Helicobacteraceae. It is normally present in the stomach.

H. pylori infections are usually the result of consuming contaminated food or water. It is spread via contaminated fecal matter. 

H. Pylori and Peptic Ulcers: Nobel Prize of 2005

The fact that H. pylori cause complications such as chronic gastritis and ulcers was established in 1982 by two Australian scientists, Barry Marshall and Robin Warren. For their outstanding work and unexpected discovery, the Nobel Prize of 2005 in Physiology or Medicine was awarded to both these scientists.

Their research dismissed the conventional belief that ulcers were a result of stress and lifestyle factors alone. They established that gastritis and ulceration of the stomach or duodenum had an underlying microbial cause. Infections are more common in developing countries. Since over 80% of affected individuals exhibit no signs or symptoms, research in this aspect is still in progress.

Moreover, the research of Marshall and Warren, along with the work of other scientists, proved that inhibition of gastric acid production alone was not a complete cure for ulcers. In order to completely heal the ulcer and inflammation, the bacteria had to be eradicated. Further studies via antibiotic treatments, epidemiological studies, and human volunteers have further strengthened the link between H. pylori and gastric illness.

H. Pylori Infection: A Chronic Condition

As mentioned before, about 50% of humans carry this gram-negative bacterium in their stomachs. In developing countries, the majority of people are usually infected.

However, it has been shown that an H. Pylori infection is mostly contracted at the early childhood stages. The most common route of infection is from the mother to the child.

This chronic condition starts at the antrum (lower part of the stomach) and, as now confirmed, it will result in chronic inflammation as well.

H. Pylori infection: Asymptomatic or Symptomatic

Whether the infection will remain asymptomatic or will cause problems depends on its severity and location in the stomach. Usually, 10-15% of individuals generally develop ulcers, more commonly in the duodenum rather than the stomach. It is now believed that chronic inflammation from H. pylori infection results in excess acid production by the non-infected upper region of the stomach. This makes the infected part more vulnerable to an ulcer, bleeding, and perforation.   

H. Pylori and Stomach Cancer

Stomach cancer is the fourth most common type of cancer globally. In some rare cases, H. pylorus has been seen to infect the corpus region of the stomach. This causes a more pronounced inflammation and increases the chances of a corpus ulcer as well as stomach cancer. Moreover, inflammation poses the risk of a significant type of lymphatic neoplasm in the stomach known as MALT (mucosa associated lymphoid tissue) lymphoma.

H. Pylori Strains: Harmless and Harmful versions

The different strains of H. pylori that exist differ significantly in various aspects, such as how they adhere to the stomach lining and their ability to trigger an inflammation.

Research relating to the underlying genetic variations that cause these differences is being conducted. This will help in developing target-specific treatment options. 

See Also: Helicobacter pylori: The Bacteria that Cause Ulcers

H. Pylori and Humans: A case of Genetic Predisposition

Similar to the concept of different strains of H. pylori, genetic variations among humans also play a key role in determining their susceptibility to illness. Research is now being focused on the minor genetic polymorphisms that affect the way an individual fights bacterial infections. Findings could help single-out high-risk patients. Studies have been conducted on an animal model, the Mongolian gerbil.

An Overview Of H. pylori Infections - Symptoms, Diagnosis, and Treatment Options

Symptoms of Helicobacter Pylori

Inflammation and ulcers caused by H. pylori may be asymptomatic or symptomatic. For the latter, the following are the most common:

• Abdominal discomfort in the upper part
• Nausea
• Vomiting
• Loss of appetite
• Bloating
• Darkening of the stool
• Blood in the stool (bleeding from the ulcer)
• Fatigue

How is H. Pylori Detected?

There are three tests that are routinely used to detect an H. pylori infection. They are:

1. Stool Test: This consists of tests that detect the presence of certain proteins that are specific to H. pylori and are passed in the stool
2. Blood Test: This test detects the antibodies that are produced by an individual’s immune system specifically in response to H. pylori.
3. Urea Breath Test: This procedure involves drinking a special solution that contains a substance which is broken down by the bacterium. The products of the breakdown are then detected in the breath.

H. Pylori Infection - Treatment Options

Antibiotic Course

Only patients who test positive for H. pylori should be treated with antibiotics. They should also be informed about the aspect of developing drug resistance if they do not take the drugs for the prescribed amount of time. This is a serious issue and is the main hindrance in the antibiotic treatment regime. Other factors, such as potential side-effects of the drugs, are also to be considered when prescribing treatment.

Triple Therapy

The approved antibiotic treatment consists of a triple therapy. This is administered for about 10-14 days. Cure rates upto 90% have been reported in cases of peptic, gastric, and even duodenal ulcers.

Each drug has its own purpose. The most commonly used triple regimes that are being used worldwide include:

• Omeprazole, Amoxicillin, Clarithromycin (OAC) for 10 days   OR
• Bismuth subsalicylate, Metronidazole, Tetracycline (BMT) for 14 days   OR
• Lansoprazole, Amoxicillin, Clarithromycin (LAC) for either 10 or 14 days

Latest discoveries have showed that Omeprazole, Amoxicillin, and Clarithromycin (OAC) show the best results. Omeprazole is a proton pump inhibitor which blocks excess acid production in stomach whereas Amoxicillin and Clarithromycin play a role in H. Pylori eradication.

Possible Side-effects

About 50% of patients experience side-effects during the antibiotic regime. These are usually minor and can be controlled by adjusting the antibiotic dosage or timing. Some of these include:

• Metallic taste in the mouth
• Blackening of stool
• Constipation
• Diarrhea
• Abdominal cramping

Consuming alcohol during the regime can also cause many distressing side-effects, such as nausea, vomiting, headaches, rapid heart rate, etc.

In-case of H. Pylori Treatment Failure

A second regime for 14 days is then administered. This comprises of:

• A proton pump inhibitor and two antibiotics.
• At least one of the antibiotics is different from those used in the first regime.

Follow-up after Treatment

A breath or stool test is generally performed to confirm the success of treatment. Blood tests are not recommended since there are chances of a false-positive result.

See Also: New Breath Test Detects H.Pylori in 10 minutes

Alternates Methods under Investigation

Quadruple Therapy

Due to the increasing resistance to antibiotics, researchers have conducted successful trials using a quadruple antibiotic regime. This consisted of Omeprazole along with a single 3-in-1 capsule containing Bismuth subcitrate potassium, Metronidazole, and Tetracycline. The results showed a better cure rate as compared to the triple therapy, along with the same safety and tolerability.

Vaccine

Researchers are also working on the development of a vaccine against H. pylori infections. This could significantly reduce the incidence of stomach cancer among susceptible individuals.