Streptococcus or Strep Bacterial Infection

Streptococcus is a common bacterium in and on our bodies. Most types of streptococci are harmless to humans, but some are responsible for diseases such as tooth decay, strep throat, impetigo, scarlet fever, rheumatic fever, pneumonia, meningitis and necrotizing fasciitis (flesh-eating disease). One type of streptococcus is beneficial, however - it’s used to create fermented foods like certain yogurts and cheeses.

Streptococcus has round cells, which are often attached to each other to form pairs or chains. Streptococci don’t need oxygen to survive. They are known as lactic acid bacteria because they feed on carbohydrates and obtain energy by converting the carbohydrates to lactic acid.

Many different species and strains of Streptococcus exist, and these are classified into different groups named after letters of the alphabet. Streptococci in Group A (GAS) live on our skin and in our throats and usually cause no problems, but they occasionally make us ill. The illnesses may be relatively mild, such as strep throat, impetigo or scarlet fever, or more serious, like rheumatic fever and necrotizing fasciitis.

Strep Throat, or streptococcal pharyngitis, generally occurs in children and young teenagers. It's spread by saliva droplets or drops of nose fluid transferred from an infected person, especially in a crowded environment. Symptoms include a red, swollen and painful throat and white patches on the tonsils. Lymph nodes may also be swollen. The sufferer may experience a fever and a headache, and sometimes nausea, vomiting and stomach pain as well. Strep throat is usually treated by antibiotics, even though the infection may go away without treatment, in order to prevent the bacteria from traveling deeper into the body and causing a more serious illness.

Not every sore throat is caused by Streptococcus. A sore throat caused by a virus won't respond to antibiotic treatment. A test called a throat swab is usually performed to confirm the presence of Streptococcus.

Impetigo is a common skin infection in children. Blisters appear on the skin, especially around the nose and mouth, but may also appear on the neck, hands, forearms and diaper area. The disease is spread by body contact or by touching items that have rubbed against the blisters, such as toys or towels. Doctors treat impetigo with a topical antibiotic (which is placed on the blisters) or with an oral antibiotic.

An untreated case of strep throat may lead to scarlet fever. Scarlet fever is not the serious disease that it once was, but it's still an unpleasant illness. The streptococcus bacteria that cause the strep throat produce a toxin that in some people causes a rash on the skin, generally starting with the face and neck and then spreading to other parts of the body. Red streaks may form in body creases. In addition to a rash and a sore throat, someone with scarlet fever may have swollen neck glands, a fever, body aches, nausea and vomiting. Antibiotics are used to treat scarlet fever.

Rheumatic fever is serious disorder that is a potential complication of a strep throat or scarlet fever infection. The illness involves inflammation of the joints, skin, heart or nervous system. It usually occurs in children and teenagers, but sometimes develops in adults too. It generally appears two to three weeks after the initial streptococcus infection. Symptoms may include joint pain and swelling, a fever, a rash, nodules under the skin, stomach pain, nosebleeds, chest pain and shortness of breath due to an inflamed heart, and jerky movements. There may be permanent damage to the heart valves. Treatment involves antibiotics and anti-inflammatory medications. Adults who develop rheumatic fever may find that they experience recurring episodes of the illness.

"Necrosis" refers to the death of body tissue. A fascia is a sheath of connective tissue that surrounds muscles. In necrotizing fasciitis (pronounced "fasheitis"), fasciae are inflamed and destroyed due to a streptococcus infection. Skin and the fat under the skin may be destroyed as well as the fasciae and muscles.

Necrotizing fasciitis is rare but potentially very serious, and may involve other types of bacteria as well as or instead of Streptococcus. The chance of developing necrotizing fasciitis increases if a person has a skin wound when they are exposed to bacteria that can cause the disease. A weakened immune system or a chronic disease such as diabetes, kidney disease, liver disease or cancer may also allow necrotizing fasciitis to develop.

Symptoms of necrotizing fasciitis include a wound that becomes very painful, red, hot and swollen. The tissue will eventually turn purple or black if the infection isn't treated. The patient may also experience a fever, chills, nausea, vomiting and diarrhea. He or she may go into shock and have organ failure.

Necrotizing fasciitis progresses rapidly and requires early and aggressive treatment. Antibiotics are given to kill bacteria. Surgery is often needed to remove dead tissue and sometimes limbs need to be amputated. Extra treatments will be required if a person is in shock or has organ damage. Hyperbaric oxygen therapy is helpful in some cases of necrotizng fasciitis. In this therapy, oxygen is forced into the patient's tissues under high pressure.

Group B Streptococci are a normal component of the large intestine bacterial population in many people, and may also live in the rectum, reproductive tract and urinary tract. The presence of the bacteria generally produces no symptoms in healthy people, but may cause disease in some people who have health problems like diabetes, cancer, liver disease or kidney disease.

If a woman with streptococci in her reproductive tract becomes pregnant, her baby may become "colonized" with the bacteria during birth. Generally this colonization causes no ill effects. However, about 1% to 2% of the babies develop a serious disease, such as pneumonia, meningitis or blood infections, which may be life-threatening. Premature babies are more susceptible to serious infection than full-term babies. Woman are often tested for the presence of a Group B Streptococcus before their baby is born. If the bacteria are present, antibiotics will be given during the birth. Doctors don't give the mother antibiotics any earlier since the bacteria may regrow before the baby is born.