Antibiotic Resistant Bacteria – know the presence of ASURAS with-in

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nightmare_bacteria_CDC

The Centers for Disease Control and Prevention (CDC) released its “landmark” report on the rising and lethal threat of antibiotic resistance, titled Antibiotic Resistance Threats in the United States, 2013.

The report describes a complex problem and the steps that must be taken to prevent catastrophic consequences.

First let us look at How antibiotics act against bacteria:

The premiere effects of antibiotics are the inhibition and killing of bacteria and other microbes that could harm or kill a human or animal. Unfortunately, the very organisms treated with antibiotics may become resistant to the antibiotics, says Donald Reinhardt, a microbiologist.

Find out why antibiotics work, and sometimes do not work, against bacteria….a comprehensive article by Dr. Donald.

bacteria_antibacterials

Types of Antibiotics and Their Antibacterial Activities

Typically, antibiotics are active against bacteria in one or more of five major ways:

  • membranes – distort and damage cause leakages of critical cell components, usually followed by death. Examples: polymyxin B, colistin.
  • walls – inhibit synthesis of the cell wall of glycopeptide or peptidoglycan. Examples: penicillin, cephalosporins, bacitracin, monobactams, carbapenems.
  • ribosomes – block, inhibit mRNA, tRNA or alter ribosomes or RNAs at ribosome. Examples: streptomycin, gentamycin, chloramphenicol.
  • nucleic acids – interfere with the structure, synthesis or functions of either RNA or DNA, or both. Examples: rifampin, naldixic acid, quinolones.
  • competitive inhibition – e.g. sulfa drugs involved with PABA and folic acid synthesis. Examples: sulfonamides, sulfadiazine.

Antibiotics That Affect Protein Synthesis and How It Happens

Listed following are some common antibacterial antibiotics that interfere with protein synthesis in one or more ways. There are unique differences in the structure and function of these different antibiotics as will be seen here.

  • Aminoglycosides – (streptomycin, gentamycin, kanamycin, amikacin, neomycin, netilmycin, tobramycin) — Inhibit initiation of protein synthesis and cause misreading of mRNA in prokaryotes and disrupt polysomes to form monosomes.
  • Macrolides – (tetracycline, minicycline, doxycycline) – Binds to the 30S subunit, block the site for binding of aminoacyl-tRNAs to the prokaryotic ribosome. Polypeptide chain cannot grow.
  • Chloramphenicol — (a natural nitrobenzene ring antibiotic that may cause aplastic anemia in patients) Inhibits the peptidyl transferase activity of the 50S ribosomal subunit of prokaryotes.
  • Erythromycin (clarithromycin, azithromycin, etc.) – Binds to the 50S subunit and inhibits translocation in prokaryotes.
  • Puromycin – Causes premature chain termination by acting as an analog of aminoacyl-tRNA in both prokaryotes and eukaryotes.

Protein synthesis is an integrated, precise series of steps and activities. Protein manufacture requires mRNA, tRNA, and the rRNA in the ribosomes with ribosomal-associated proteins. Disruption of this integrated system makes protein synthesis impossible, or so dysfunctional, that the cells become immobilized in growth (stasis), or are so severely damaged that they die. Either way, phagocytosis by macrophages (monocytes) and neutrophils internalizes bacteria and other microbes, and results in the destruction of the bacteria within by basic host mechanisms.

Microbial Resistance to Antibacterial, Anti-Protein-Synthesis Antibiotics, Mutation and Selection

Bacteria have very rapid division rates. Escherichia coli may divide as often as every 12-15 minutes under optimal conditions. Further, bacteria mutate to resistance at a rate of 1 in a million, to 1 in 10 million. Therefore, it is possible that some resistant mutants may have formed – even in the absence of any antibiotic. When the antibiotic is present these antibiotic-resistant mutants continue to grow, multiply and prosper.

What mechanisms do bacteria employ to become resistant to antibiotics that inhibit protein synthesis?

  • Membrane changes block entrance and penetration of the antibiotic into the cell’s cytoplasm.
  • Enzymes degrade the antibiotic, or inactivate it by reactions of: phosphorylation, adenylation, or acetylation.
  • Ribosomes with altered, mutated, chemical structures prevent antibiotic attachment to those types of ribosomes.
  • Molecular pumps energetically transfer the antibiotic out of the cell.

Antibiotics are amazing and complicated, and represent the constant, major battle to kill microbial pathogens. Bacteria, with their specialized molecular mechanisms, may inactivate some antibiotics and outflank some of science’s and medicine’s best attempts to totally control these agents of disease.

Sources: Brooks, G.F., J.S. Butel and S. A. Moore. 2004. Medical Microbiology. 23rd ed., Lange Medical Books, McGraw-Hill, New York. 818pp

Summary of The CDC’s “landmark report”

Bacterial_infections_and_involved_species

 

Antibiotic resistance is a worldwide problem

Antimicrobial resistance is one of our most serious health threats, says Dr. Tom Frieden, MD, MPH, Director, U.S. Centers for Disease Control and Prevention. Infections from resistant bacteria are now too common, and some pathogens have even become resistant to multiple types or classes of antibiotics (antimicrobials used to treat bacterial infections). The loss of effective antibiotics will undermine our ability to fight infectious diseases and manage the infectious complications common in vulnerable patients undergoing chemotherapy for cancer, dialysis for renal failure, and surgery, especially organ transplantation, for which the ability to treat secondary infections is crucial.

New forms of antibiotic resistance can cross international boundaries and spread between continents with ease. Many forms of resistance spread with remarkable speed. World health leaders have described antibiotic-resistant microorganisms asnightmare bacteriathat “pose a catastrophic threat” to people in every country in the world.

Antibiotic (mis)use: fact sheet

  • The use of antibiotics is the single most important factor leading to antibiotic resistance around the world.
  • Antibiotics are among the most commonly prescribed drugs used in human medicine.
  • Up to 50% of all the antibiotics prescribed for people are not needed or are not optimally effective as prescribed.
  • Antibiotics are also commonly used in food animals to prevent, control, and treat disease, and to promote the growth of food-producing animals.
  • The use of antibiotics for promoting growth is not necessary, and the practice should be phased out. Recent guidance from the U.S. Food and Drug Administration (FDA) describes a pathway toward this goal. It is difficult to directly compare the amount of drugs used in food animals with the amount used in humans, but there is evidence that more antibiotics are used in food production.
  • The other major factor in the growth of antibiotic resistance is spread of the resistant strains of bacteria from person to person, or from the non-human sources in the environment, including food.

There are four core actions that will help fight these deadly infections:

  1. preventing infections and preventing the spread of resistance
  2. tracking resistant bacteria
  3. improving the use of today’s antibiotics
  4. promoting the development of new antibiotics and developing new diagnostic tests for resistant bacteria

Where Do Infections Happen

Antibiotic-resistant infections can happen anywhere. Data show that most happen in the general community; however, most deaths related to antibiotic resistance happen in healthcare settings, such as hospitals and nursing homes.

What the Patients and their loved ones can do:

If infected by:

  1. Acinetobacter: is a type of gram-negative bacteria that is a cause of pneumonia or bloodstream infections among critically ill patients. Many of these bacteria have become very resistant to antibiotics.
  2. Candidiasis is a fungal infection caused by yeasts of the genus Candida. There are more than 20 species of Candida yeasts that can cause infection in humans, the most common of which is Candida albicans. Candida yeasts normally live on the skin and mucous membranes without causing infection. However, overgrowth of these microorganisms can cause symptoms to develop. Symptoms of candidiasis vary depending on the area of the body that is infected. Candida is the fourth most common cause of healthcare-associated bloodstream infections in the United States. In some hospitals it is the most common cause. These infections tend to occur in the sickest of patients.
  3.  Enterococcicause a range of illnesses, mostly among patients receiving healthcare, but include bloodstream infections, surgical site infections, and urinary tract infections.
  4.  Pseudomonas aeruginosais a common cause of healthcare-associated infections including pneumonia, bloodstream infections, urinary tract infections, and surgical site infections.
  5. Methicillin-resistantStaphylococcus aureus (MRSA) causes a range of illnesses, from skin and wound infections to pneumonia and bloodstream infections that can cause sepsis and death. Staph bacteria, including MRSA, are one of the most common causes of healthcare-associated infections.
  6. Staphylococcus aureusis a common type of bacteria that is found on the skin. During medical procedures when patients require catheters or ventilators or undergo surgical procedures, Staphylococcus aureus can enter the body and cause infections. When Staphylococcus aureus becomes resistant to vancomycin, there are few treatment options available because vancomycin-resistant S. aureus bacteria identified to date were also resistant to methicillin and other classes of antibiotics.
      • In these cases, follow the following tips:
        • Ask everyone including doctors, nurses, other medical staff, and visitors, to wash their hands before touching the patient.
        • Take antibiotics only and exactly as prescribed.

If infected by:

  1. Salmonella serotype Typhi: causes typhoid fever, a potentially life-threatening disease. People with typhoid fever usually have a high fever, abdominal pain, and headache. Typhoid fever can lead to bowel perforation, shock, and death.
      • In these cases, follow the following tips:
        • If you’re traveling to a country where typhoid fever is common:
          • Get vaccinated against typhoid fever before you depart.
          • Choose foods and drinks carefully while traveling even if you are vaccinated. That means: boil it, cook it, peel it, or forget it.If you get sick with high fever and a headache during or after travel, seek medical care at once and tell the healthcare provider where you have traveled.
          • Boil or treat water yoursel
          • Eat foods that are hot and steaming
          • Avoid raw fruits and vegetables unless you peel them yourself
          • Avoid cold food and beverages from street vendors.

If infected by:

  1. Campylobacter: usually causes diarrhea (often bloody), fever, and abdominal cramps, and sometimes causes serious complications such as temporary paralysis.
  2. Non-typhoidal Salmonella (serotypes other than Typhi, Paratyphi A, Paratyphi B, and Paratyphi C) usually causes diarrhea (sometimes bloody), fever, and abdominal cramps. Some infections spread to the blood and can have life-threatening complications.
      • In these cases, follow the following tips:

        • Clean. Wash hands, cutting boards, utensils, and countertops.
        • Separate. Keep raw meat, poultry, and seafood separate from ready-to-eat foods.
        • Cook. Use a food thermometer to ensure that foods are cooked to a safe internal temperature.
        • Chill. Keep your refrigerator below 40°F and refrigerate food that will spoil.
        • Avoid drinking raw milk.
        • Report suspected illness from food to your local health department.
        • Don’t prepare food for others if you have diarrhea or vomiting.
        • Be especially careful preparing food for children, pregnant women, those in poor health, and older adults.
        •  Consume safe food and water when traveling abroad.

If infected by:

  1. Shigella usually causes diarrhea (sometimes bloody), fever, and abdominal pain. Sometimes it causes serious complications such as reactive arthritis. High-risk groups include youngchildren, people with inadequate handwashing and hygiene habits, and men who have sex with men.
      • In these cases, follow the following tips:

        • Don’t prepare food for others if you have diarrhea or vomiting.
        • Keep children who have diarrhea and who are in diapers out of child care settings and swimming pools.
        • Avoid sexual behavior that is likely to transmit infection when you have diarrhea.
        • Consume safe food and water when traveling abroad.

If infected by:

  1. Streptococcus pneumoniae (S. pneumoniae, or pneumococcus) is the leading cause of bacterial pneumonia and meningitis in the United States. It also is a major cause of bloodstream infections and ear and sinus infections.
  2. Group A Streptococcus (GAS) causes many illnesses, including pharyngitis (strep throat), streptococcal toxic shock syndrome, necrotizing fasciitis (“flesh-eating” disease), scarlet fever, rheumatic fever, and skin infections such as impetigo.
      • In these cases, follow the following tips

        • Prevent infections by getting recommended vaccines and practicing good hand hygiene.
        • Take antibiotics exactly as the doctor prescribes. Do not skip doses. Complete the prescribed course of treatment, even when you start feeling better.
        • Only take antibiotics prescribed for you; do not share or use leftover antibiotics.
        • Do not save antibiotics for the next illness. Discard any leftover medication once the prescribed course of treatment is completed.
        • Do not ask for antibiotics when your doctor thinks you do not need them.

If infected by:

  1. Group B Streptococcus (GBS) is a type of bacteria that can cause severe illnesses in people of all ages, ranging from bloodstream infections (sepsis) and pneumonia to meningitis and skin infections.
      • In these cases, follow the following tips:

        • Pregnant women should talk to their doctor or nurse about their GBS status and let them know of any medication allergies during a checkup.
        • When women get to the hospital or birthing center for delivery, they should remind their doctor or nurse if they have GBS and if they are allergic to any medications.
        • Practice appropriate antibiotic use whenever you see a doctor or are prescribed  an antibiotic for any condition:
          • Take antibiotics exactly as the doctor prescribes. Do not skip doses. Complete the prescribed course of treatment, even when you start feeling better.
          • Only take antibiotics prescribed for you. Do not share or use leftover antibiotics.
          • Do not save antibiotics for the next illness. Discard any leftover medication
            once the prescribed course of treatment is completed.
          • Do not ask for antibiotics when your doctor thinks you do not need them.

If infected by:

Tuberculosis (TB) is among the most common infectious diseases and a frequent cause of death worldwide. TB is caused by the bacteria Mycobacterium tuberculosis (M. tuberculosis) and is spread most commonly through the AIR. M. tuberculosis can affect any part of the body, but disease is found most often in the lungs. In most cases, TB is treatable and curable with the available first-line TB drugs; however, in some cases, M. tuberculosis can be resistant to one or more of the drugs used to treat it. Drug-resistant TB is more challenging to treat — it can be complex and requires more time and more expensive drugs that often have more side effects. Extensively Drug-Resistant TB (XDR TB) is resistant to most TB drugs; therefore, patients are left with treatment options that are much less effective. The major factors driving TB drug resistance are incomplete or wrong treatment, short drug supply, and lack of new drugs. In the United States most drug-resistant TB is found among persons born outside of the country.

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Regarding level of concern, CDC has — for the first time — prioritized bacteria in this report into one of three categories: urgent, serious, and concerning. Threats assigned to the urgent and serious categories require more monitoring and prevention activities

HAZARD LEVEL “URGENT”

Clostridium difficile (C. difficile),

Carbapenem-resistant Enterobacteriaceae (CRE),

Drug-resistant Neisseria gonorrhoeae (cephalosporin resistance)

HAZARD LEVEL “SERIOUS”

Multidrug-resistant Acinetobacter,

Drug-resistant Campylobacter,

Fluconazole-resistant Candida (a fungus),

Extended spectrum β-lactamase producing Enterobacteriaceae (ESBLs),

Vancomycin-resistant Enterococcus (VRE),

Multidrug-resistant Pseudomonas aeruginosa,

Drug-resistant Non-typhoidal Salmonella,

Drug-resistant Salmonella Typhi, Drug-resistant Shigella, Methicillin-resistant Staphylococcus aureus (MRSA),

Drug-resistant Streptococcus pneumonia,

Drug-resistant tuberculosis (MDR and XDR)

HAZARD LEVEL “CONCERNING”

Vancomycin-resistant Staphylococcus aureus (VRSA),

Erythromycin-resistant Streptococcus Group A,

Clindamycin-resistant Streptococcus Group B

The actual number of infections and the actual number of deaths

are certainly higher than the numbers provided in this report.”

and/or

“The estimates provided in this report represent an underestimate of the total burden of bacterial resistant disease”

Read The Full Report

News Source: Medscape

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