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Methicillin-Resistant Staphylococcus Aureus (Mrsa) Infection -Symptoms, Causes, Diagnosis, and Treatment

Published on Dec 30, 2019   -  5 min read


MRSA (Methicillin-resistant Staphylococcus aureus) infections are a group of infections that are caused by antibiotic-resistant Staphylococcus, which are challenging to treat. Learn about its symptoms, types, diagnosis, and treatment.

Methicillin-Resistant Staphylococcus Aureus (Mrsa) Infection -Symptoms, Causes, Diagnosis, and Treatment

Quick Facts:

  1. MRSA can result in antibiotic-resistant bacterial infection.

  2. Most people get infected with MRSA in hospital settings.

  3. Staphylococcus aureus bacteria commonly resides inside the nose of one in three people, and MRSA is found in two out of 100 people.

  4. Antibacterial wipes and gels used in hospitals have significantly reduced MRSA infection.

  5. Staph infection is the most common cause of skin infections like pimples, abscesses, wound infections, boils, and impetigo.

What Is MRSA?

Methicillin-resistant Staphylococcus aureus, otherwise called MRSA or superbug, is a group of bacteria that cause severe infections in humans, which is difficult to treat. They are a genetically modified form of other Staphylococcus aureus strains. Any strain of Staphylococcus aureus can undergo genetic mutation and become resistant to multiple beta-lactam antibiotics, such as Methicillin, Penicillin, Amoxicillin, Oxacillin, and Cephalosporins. As these broad-spectrum antibiotics cannot treat infection caused by MRSA, it becomes challenging to treat.

What Is MRSA Infection?

MRSA can be found naturally in the nose, skin, and gut, and do not cause infection under normal circumstances. When they start to multiply uncontrollably, it results in MRSA infection. They enter the body through a cut or injury and are highly contagious through person to person contact, or using or touching objects used by an infected person. This infection can be effectively treated with some antibiotics, even though it is resistant to most antibiotics.

MRSA infection commonly affects hospitalized patients or patients in other health care facilities or nursing homes or dialysis centers. When a patient acquires this infection in a hospital through surgeries, catheters, or artificial joints, it is called healthcare-associated MRSA (HA-MRSA). And MRSA infection that affects healthy people living in a crowded environment is called community-associated MRSA (CA-MRSA). This infection often starts as a painful skin boil.

What Are the Symptoms of MRSA Infection?

MRSA or all other Staph infection starts as a swollen and painful red bump, which resembles a pimple or insect bite. The skin surrounding these bumps is warm to touch, may drain pus, and the person will have a fever.

These boils turn into painful abscesses, which need to be surgically drained. In rare cases, bacteria go deep into the body and cause fatal infections in the heart, lungs, bones, urinary tract, joints, surgical incisions, and blood.

The symptoms of deep or severe MRSA infection are:

What Causes MRSA infection?

There are numerous varieties of Staphylococcus aureus bacteria found in nature. They live on the skin and inside the nose and are harmless until they enter the body through a cut or wound. If they do enter, it results in minor skin infection in healthy individuals. Staph infection is the most common cause of skin infection worldwide.

The unnecessary and indiscriminate use of antibiotics for decades has made some Staph aureus resistant, giving rise to MRSA. Taking antibiotics for colds, flu, and viral infections result in this resistance. Apart from this, taking antibiotics for bacterial infection also increases the number of drug-resistant bacteria, because antibiotics do not kill all bacteria present in the body. Bacteria that are still present after the course of antibiotics develop resistance to other antibiotics.

What Are the Risk Factors for MRSA Infection?

The risk factors for hospital-acquired MRSA (HA-MRSA) are:

  1. Immunocompromised patients - hospitalized older adults and people with a weak immune system are at risk of acquiring MRSA infection.

  2. Patients with kidney failure - regular dialysis increases the risk of MRSA infection.

  3. Invasive medical devices - like IV (intravenous) lines or urinary catheters make it easy for bacteria to enter the body.

  4. Patients in healthcare facilities - MRSA can get transferred from one person to another, even if the person is just a carrier and not infected.

The risk factors for community-acquired MRSA (CA-MRSA) are:

  1. Overcrowded community - living in an overcrowded and unhygienic environment can result in MRSA infection. Examples include child care centers, military camps, and jails.

  2. Contact sports - the infection can spread through cuts and abrasions through skin contact or coming in contact with infected or pus-filled boils on the skin.

  3. Injectable recreational drugs - People who use recreational intravenous medicines are 16.3 times more likely to develop deep and severe MRSA infections.

  4. Homosexual men - Men who have sex with other men are at a higher risk of developing this infection.

  5. Sharing personal equipment like razors and towels.

How Is MRSA Infection Diagnosed?

The doctor will first take a medical history and conduct a complete physical examination. To diagnose MRSA, the doctor might collect one or more of the following samples for culture:

  1. Sample from the wound is taken with a cotton swab.

  2. Sputum is collected by asking the patient to cough, which is then checked for bacteria, blood, and pus. For patients who are on ventilators or those unable to cough up sputum, respiratory lavage or bronchoscopy is done to collect sputum.

  3. For urine culture, a urine sample is collected and sent to a lab. Sometimes, urine is collected directly from the bladder by inserting a catheter into the bladder.

  4. Blood can also be drawn and sent for blood culture to identify the causative bacteria.

How Is MRSA Infection Treated?

Both HA-MRSA and CA-MRSA are treated differently.

  1. HA-MRSA - IV antibiotics are given for a long time or depending on the severity of the infection.

  2. CA-MRSA - Here, oral antibiotics are usually sufficient to treat the infection.

If an abscess has developed, the doctor will perform incision and drainage under local anesthesia.

What Are the Complications of MRSA Infections?

Staph infection can spread deeper and can result in the following fatal conditions:

Preventive Measures:

For more information on MRSA infection, consult a doctor online now!

Frequently Asked Questions


What Is MRSA?

An MRSA is an abbreviation of Methicillin-resistant staphylococcus aureus, a bacteria resistant to many antibiotics. It can cause various problems ranging from skin infections, sepsis, and pneumonia to bloodstream infections.


Is MRSA A Contagious Disease?

Yes, MRSA is a contagious disease that can spread from person to person by direct contact. However, it can also spread through indirect contact because the bacteria can survive on objects like towels, shaving equipment, benches, and other things.


What Drugs Are MRSA Resistant To?

MRSA is a common and potentially severe infection that has developed resistance to several types of antibiotics. These include Methicillin and related antibiotics, such as Penicillin, Vancomycin, and Oxacillin. This resistance makes MRSA challenging to treat.


What Can Be the First Signs of MRSA?

The first signs of MRSA are:
- Painful lesion that is purulent, compressible, and fluid-filled.
- Boil or sore (abscess) that leaks fluid.
- Painful sore along with a fever.
- Bumps that are painful, red, leaking fluid, or swollen. It may look like a pimple, boil, or a spider bite.
- Swollen or firm bumps under the skin.
- The skin around a sore is warm or hot.
- Bump that gets more prominent quickly or does not heal.
- Rash or fluid-filled blisters.


What Is the Most Potent Antibiotic for MRSA

The most commonly used and the strongest antibiotic for the treatment of MRSA infection is Vancomycin. It is a very effective drug, and the response to the treatment is quick and outstanding.


Can MRSA Go Away Permanently?

In many people, MRSA with active infections are treated effectively and no longer exist. However, sometimes MRSA, which goes away after treatment, can come back several times. If MRSA infections repeatedly recur, consult with your doctor to figure out why you keep getting them.


What Can Kill MRSA in the Body?

According to a study in mice and rats, molecules produced by a bacterium living in the human nose can kill the potentially deadly methicillin-resistant Staphylococcus aureus (MRSA).


How Long Does a Person With MRSA Remain Contagious?

MRSA is contagious as long as viable MRSA bacteria in or on an individual colonized with these bacteria or infected with the organisms. Therefore, a person colonized with MRSA (one who has the organism usually present inside or outside the body) may be contagious for a more extended period.


Can We Cure MRSA?

Even though MRSA is challenging to treat since it is resistant to many antibiotics, decolonization and a few antibiotics can cure MRSA infections. Standard treatment like using an oral Chlorhexidine rinse, Mupirocin nasal ointment, and a full-body wash using Chlorhexidine soap for five days can cure MRSA. Urinary tract and intestinal colonies are treated with the combination of Vancomycin (oral) and Sulfonamides, such as Cotrimoxazole, and vaginal colonies are treated with an Octenidine solution. Successful decolonization is determined to be achieved only when the results are negative for three consecutive sets of cultures. Therefore, a standardized regimen for MRSA decolonization is very effective in people who fully complete the treatment.


Which Internal Organ Is Most Affected by MRSA?

The skin is the most affected part of the body by this condition, where the bacteria can cause blisters, boils, hair root infection, and peeling of the skin. If not monitored or treated correctly, it can affect the body's blood, bones, and major organs like the heart and lungs.


Can MRSA Go Away on Its Own?

The MRSA can go away on its own. But, the doctor may order for a particular antibiotic cream to be applied to the nose and on any wounds present. You must apply this cream as prescribed for the recommended period and wash your body with a special skin antiseptic soap.


Is It Necessary For an MRSA Patient To Be Isolated?

MRSA patients need to be isolated because being treated in the same room as or close to another patient with MRSA can also increase a patient's risk of acquiring MRSA. The bacteria can also spread on unclean hands or medical equipment.


Can You Go to Work if You Have MRSA?

It is not necessary to get excluded from going to work unless directed by a healthcare provider. However, exclusion from work should be reserved only for those with wound drainage that cannot be adequately secured and contained with a clean, dry bandage and those who cannot maintain good hygiene practices.


What Will Happen When You Test Positive For MRSA?

If your test result shows MRSA positive, it means you have an MRSA infection. You can continue with your daily work but, you need to follow a few essential guidelines to avoid MRSA from causing further problems or complications. The treatment usually depends on the severity of the infection. However, your doctor will recommend treatments, including antibiotics intake and draining of sores if you have an infection. For mild skin infections, your provider may clean, drain, and cover the wound.


Is MRSA an Airborne Disease?

Airborne methicillin-resistant Staphylococcus aureus (MRSA) have previously been found on pig farms, which may lead to nasal deposition of MRSA in humans via inhalation. The anterior nares are the main niche for S. aureus and S. aureus, which can cause wound infection and pneumonia.


How To Differentiate Between an MRSA and a Pimple?

- MRSA pimples are more similar to boils than acne pimples.
- MRSA pimples will not respond to any standard acne treatments like
- Benzoyl peroxide or Salicylic acid.
- MRSA pimples will more closely be situated around cuts or breaks in the skin.
- MRSA pimples will be more painful than acne pimples.
- MRSA pimples are often surrounded by areas of inflammation, redness, and warmth.
- Fever often accompanies the outbreak of MRSA pimples.
- The MRSA pimples can appear anywhere on the body and involve just a single lesion, but the acne tends to crop up in the same few places on the body, like the face, back, chest, and shoulders and will not be accompanied by fever.

Article Resources

Last reviewed at:
30 Dec 2019  -  5 min read




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