Sunday, July 31, 2011

The End!

This truthfully has been a great semester, and a great learning experience. I really wish had more time to put into in, because I honestly think i have learned tremendously from all this material during this class. I honestly never thought I would even be able to look at a plate with 3 or 4 organisms and would be able to differentiate between all of them.
I enjoyed this class with everyone, hopefully someone has learned something new from my posts.
I really liked this idea of doing blogs, because I honestly had to search and think about new ideas and materials every time, and that expands my learning exponentially in the topic area. Even though sometimes it was hard for me to come up with something different for both the lecture and lab.
This has been a great experience, and hope to see you all next semester.
Good luck everyone on your finals!!!!!!

Sunday, July 24, 2011

CDC Guidance for Clinical Laboratories for conducting Influenza Testing

This past week our topic was the Laboratory Methods in Basic Virology. Influenza virus, especially the H1N1 strand, has caused an epidemic worldwide during the last few years. I will be discussing in this thread the CDC guidance for processing of influenza testing in the clinical laboratory.

Many different laboratory diagnostic tests can be used for detecting the presence of influenza viruses in respiratory specimens. These tests include direct antigen detection tests, virus isolation in cell culture, or detection of influenza-specific RNA by rRT-PCR methods.  
At this time, there are only two FDA approved assays for confirmation of novel influenza A(H1N1) virus infection, including the CDC rRT-PCR Swine Flu Panel assay. Confirmation of influenza A(H1N1) infection may be necessary for surveillance purposes and for special situations, such as immunocompromised patients or in pregnancy.

Rapid influenza diagnostic tests (RIDTs) are antigen detection tests that detect the influenza viral nucleoprotein antigen, and these assays are point of care tests.  Some of these tests, with high sensitivity and specificity, can detect and distinguish between influenza A and B viruses, but none can distinguish between the different subtypes.  The sensitivities of RIDTs to detect influenza B viruses are lower than for detection of influenza A viruses.  The sensitivities of RIDTs appear to be higher for specimens collected from children than specimens collected from adults.
Compared to RT-PCR, the sensitivity of RIDTs for detecting novel influenza A (H1N1) virus infections ranged from 10-70%. Therefore, a negative RIDT result does not rule out novel influenza A (H1N1) virus infection. The type of respiratory specimen (i.e., nasal vs. nasopharyngeal swab), quality of the specimen, time from illness onset to specimen collection, the age of the patient, time from specimen collection to testing, and the storage and processing of the specimen prior to testing, all are factors that contribute to the sensitivity of these tests.


Positive test result with RIDT indicates that the influenza virus infection is likely present in the specimen.  A negative rapid test result does not rule out influenza virus infection, and clinical presentation should always be taken into consideration. 
The specificity of RIDTs is generally high. However, especially during periods of low influenza activity (e.g. the very beginning of the season), however false positive results can occur.
The CDC recommends adding a statement when about the test limitations in the report of results so that the physician can decide how best to use the test for patient management.



"Example of a Statement to Accompany Rapid Influenza Diagnostic Test Results
RIDT result: Positive for Influenza Type A 
Note: This test can not distinguish influenza A virus subtypes.  For example, this test cannot distinguish influenza infections caused by novel influenza A viruses versus seasonal influenza A viruses.

RIDT result: Negative for Influenza A and B
Note:  The sensitivity of this assay has been shown to range between [10-70%*] for the detection of novel influenza A (H1N1) virus and between [20-100%*] for seasonal influenza viruses. A negative result does not exclude influenza virus infection. If influenza is circulating in your community, a diagnosis of influenza should be considered based on a patient’s clinical presentation and empiric antiviral treatment should be considered, if indicated.  If more conclusive testing is desired, follow-up confirmatory testing with either [viral culture or RT-PCR*] is warranted".


http://www.cdc.gov/h1n1flu/guidance/rapid_testing.htm

Monday, July 18, 2011

CLSI definitions for Succeptibility testing - Lab week 7

As everyone remembers, we  have done susceptibility testing this week during lab. 
The test is performed by applying a bacterial inoculum to the surface of a large Mueller-Hinton agar plate. After the plates have been inoculated  for 16–24 h at 35°C prior to determination of results, the susceptibility of each on the antimicrobials was graded according to the diameter of the inhibition zone, and then susceptibility was graded as either susceptible, intermediate and resistant. The diameter of the zone is related to the susceptibility of the isolate and to the diffusion rate of the drug through the agar medium.
According to the CLSI, those categories each has a certan clinical implication:
Susceptible

'The "susceptible" category implies that isolates are inhibited by the usually achievable concentrations of antimicrobial agent when the recommended dosage is used for the site of infection.
 
Resistant

'The "resistant" category implies that isolates are not inhibited by the usually achieveable concentrations of the agent with normal dosage schedules, and/or that demonstrate zone diameters that fall in the range where specific microbial resistance mechanisms (e.g. beta-lactamases) are likely, and clinical efficacy of the agent against the isolate has not been reliably shown in treatment studies.
 
Intermediate

'The "intermediate" category includes isolates with antimicrobial MICs that approach usually attainable blood and tissue levels and for which response rates may be lower than for susceptible isolates. The intermediate category implies clinical efficacy in body sites where the drugs are physiologically concentrated. This category also includes a buffer zone, which should prevent small, uncontrolled, technical factors from causing major discrepancies in interpretations, especially for drugs with narrow pharamacotoxicity margins.
 
 

Saturday, July 16, 2011

Antibiotic Resistance news articles + CDC MASTER program - Week 7

Our main topic during this week lecture focused on antimicrobial resistance and the rise of resistant strains to the different drug regimen that we have available currently; from HIV, to MRSA, N. gonorrhea and others, this is becoming a major health concern and is causing a rise in patient morbidity and mortality, and a huge rise in healthcare cost.
I have taken advantage of this and looked up some articles in the news about the rise of antibiotic resistance and its impact on healthcare.

Furthermore, the CDC have initiated the Multi-level Antimicrobial Susceptibility Testing Resources (MASTER) program which is responsible of publishing resources, case studies, reference materials, news and others about such incidences. Please refer to the following link:

http://wwwn.cdc.gov/dls/master/archives.aspx?type=1


Below is an article published in USA today regarding this topic.

http://www.usatoday.com/news/health/2002-09-29-drugs-usat_x.htm

Antibiotic resistance on the rise
In the battle between bugs and drugs, the bugs are scoring some big wins.
Scientists here at an international meeting of the American Society for Microbiology warn that disease-causing microbes are becoming immune to a growing list of antibiotics, and new antibiotics and vaccines are barely keeping ahead of them.
"There are patients today in hospitals for whom there are no effective therapies," says Gary Doern, director of clinical microbiology at the University of Iowa, a panelist at a briefing here of the International Forum on Antibiotic Resistance.
Until recently, almost all drug-resistant bacteria were confined to hospitals, where a concentration of sick people and high antibiotic use contributed to the evolution of strains capable of evading antibiotic attack.
Now, Doern says, it's not uncommon for patients to come in the door carrying drug-resistant microbes that are circulating in the community. Among concerns highlighted by doctors at the Interscience Conference on Antimicrobial Agents and Chemotherapy:
  • Methicillin-resistant Staphylococcus aureus, or MRSA, accounts for more than half of hospital-acquired bloodstream infections caused by staph. In some cities, 31% of such infections outside the hospital are methicillin-resistant, and in nursing homes, 71% of staph infections are MRSA.
  • In some areas, about 50% of Campylobacter bacteria, the most common cause of diarrhea, are resistant to Cipro.
  • About a third of the germs most commonly responsible for severe pneumonia, Streptococcus pneumoniae, are resistant to penicillin in the USA, and about 25% are resistant to multiple drugs.
  • Resistance to fluoroquinolones, a newer class of drugs, also is on the rise. Researchers in Toronto reported Sunday that in 2001, 1.2% of the S. pneumoniae bacteria in Canada were resistant to levofloxacin, a fluoroquinolone introduced in 1996, compared with 0.9% in 2000 and 0.4% in 1999.
"We are living in a time where increasing drug resistance is frustrating treatment of common infections," says Roger Finch, professor of infectious diseases at England's University of Nottingham. "It is having an impact on hospitals and forcing us to use (antibiotics) we might have kept in reserve" to use only against the most persistent infections.
Antibiotics wipe out bacteria that are susceptible to them. But when used improperly, they can encourage the growth of bacteria that have adapted to them. And because bacteria can swap genes under the right conditions, drug-resistant germs can share their resistance mechanisms with other germs.
That is what is thought to have happened in the case of a Michigan woman reported this summer. She acquired the USA's first case of Staphylococcus aureus, a common bloodstream and skin infection, that was impervious to the antibiotic vancomycin, says Michael Rybak of Wayne State University in Detroit. Vancomycin has been known as the drug of last resort; it is used to treat infections that don't respond to other drugs. But in recent years, it has been used so often that intestinal bacteria called enterococci have become resistant.
The Michigan patient already was infected with vancomycin-resistant enterococci, and those microbes might have passed their drug-resistance mechanisms to the staph bacteria, creating what doctors call a "superbug."
As bacteria evolve resistance to more classes of antibiotics, drug companies are racing to create new ones. Rybak presented data Saturday showing that a drug being developed by Cubist Pharmaceuticals, daptomycin, was effective against vancomycin-resistant S. aureus.
Company officials say the drug has been tested in more than 2,500 patients, and they hope it will be reviewed for licensing within a year. In other studies, researchers reported that another new antibiotic, telithromycin, is effective in treating drug-resistant pneumonia.
Though new antibiotics are welcome, doctors say that unless patients and health care professionals learn to use them more carefully, the bugs will continue to outsmart the drugs.
Education strategies in hospitals and in communities, aimed at both doctors and patients, are achieving success in reducing overuse and misuse of antibiotics, researchers say.
"If we use antibiotics, some level of antibiotic resistance will emerge," Doern says. To slow that down, "we should use antibiotics only when needed, and, when needed, use the right one."

Monday, July 11, 2011

Thio broth- Lab

infections with Pasteurella multocida

http://f12network.com/craig/microbiology/0809S1/ch27_md/index_md.htm#Pasteurella%20Multocida


Pasteurella multocida is a bacteria belonging to the Pasteurellaceae family; it is a Gram-negative, non-motile coccobacillus that is often present in the upper respiratory tracts of many livestock, poultry, and domestic pets such as cats and dogs. 

According to the American Pet Association, approximately 10% of animal bites require medical attention; 1-2% eventually requires hospitalization. 
One of the most common symptoms of infection with P. multocida is respiratory infection manifesting as a nasal discharge, sneezing, congestion, conjunctivitis, and clogged tear ducts. Pasteurella infections also can cause abscesses under the skin that can be chronic, requiring surgery to correct. Some abscesses can cause central nervous symptoms like nystagmus, circling to one side, and wryneck or torticollis. 









http://emedicine.medscape.com/article/224920-overview

P. multocida  is a facultative anaerobe, which will grow at 37 degrees Celsius on blood or chocolate agar, but will not grow on MacConkey agar. Colony growth is characterized with a  "mousy" odor due to metabolic products. it is oxidase-positive and catalase-positive.

P. multocida virulence factor is due to a toxin, known as "Pasteurella multocida mitogenic toxin", which activates Rho GTPases, which then bind and hydrolyze GTP, and are important in actin stress fiber formation. This eventually leads to cytoskeletal reorganisation. 

Most Pasteurella isolates are susceptible to oral antimicrobial treatment with  one of the following drugs, or in combination: amoxicillin, amoxicillin/clavulanic acid, minocycline, fluoroquinolones (ciprofloxacin, ofloxacin, levofloxacin, moxifloxacin), and trimethoprim-sulfamethoxazole. 

Infections with P. multocida are mainly due to animal bites. Below are the organisms that can be found in different bites from animals, please refer to medscape article: “Animal Bites in Emergency Medicine.”

  • Dog bites
    • Staphylococcus species
    • Streptococcus species
    • Eikenella species
    • Pasteurella species
    • Proteus species
    • Klebsiella species
    • Haemophilus species
    • Enterobacter species
    • DF-2 or Capnocytophaga canimorsus
    • Bacteroides species
    • Moraxella species
    • Corynebacterium species
    • Neisseria species
    • Fusobacterium species
    • Prevotella species
    • Porphyromonas species
  • Cat bites
    • Pasteurella species
    • Actinomyces species
    • Propionibacterium species
    • Bacteroides species
    • Fusobacterium species
    • Clostridium species
    • Wolinella species
    • Peptostreptococcus species
    • Staphylococcus species
    • Streptococcus species
  • Herbivore bites
    • Actinobacillus lignieresii
    • Actinobacillus suis
    • Pasteurella multocida
    • Pasteurella caballi
    • Staphylococcus hyicus subsp hyicus
  • Swine bites
    • Pasteurella aerogenes
    • Pasteurella multocida
    • Bacteroides species
    • Proteus species
    • Actinobacillus suis
    • Streptococcus species
    • Flavobacterium species
    • Mycoplasma species
  • Rodent bites - Rat-bite fever
    • Streptobacillus moniliformis
    • Spirillum minus
  • Primates
    • Bacteroides species
    • Fusobacterium species
    • Eikenella corrodens
    • Streptococcus species
    • Enterococcus species
    • Staphylococcus species
    • Enterobacteriaceae
    • Simian herpes virus
  • Large reptiles (crocodiles, alligators)
    • Aeromonas hydrophila
    • Pseudomonas pseudomallei
    • Pseudomonas aeruginosa
    • Proteus species
    • Enterococcus species
    • Clostridium species


Other references:
http://www.copewithcytokines.org/cope.cgi?key=Pasteurella%20multocida%20toxin


 

Monday, July 4, 2011

BactiCard Neisseria - Lab

I am going to dedicate this section to discuss the main test done to identify the different Neisseria species, and that most of us had to do during lab this past week. 

The BactiCard Neisseria is a chromogenic enzyme substrate system for identifying Neisseria gonorrhoeae, Neisseria meningitidis, Neisseria lactamica, and Moraxella catarrhalis. The identification system consists of a card with four test circles impregnated with chromogenic substrates for indoxyl butyrate esterase (IB) for Moraxella catarrhalis, prolyl aminopeptidase (PRO) for Neisseria gonorrhoeae, gamma-glutamyl aminopeptidase (GLUT) for Neisseria meningitidis, and ss-galactosidase (BGAL) for Neisseria lactamica

After hydration of the circles with buffer, colonies from growth on selective media or a subculture are applied to the four circles. The IB reaction is read for a blue-green color after 2, then the BGAL reaction is read at 15 min, also for blue-green color change. PRO and GLUT reactions are read at 15 min for a red color after addition of a developer reagent. 

The following picture shows positive results on BactiCard Neisseria for M. catarrhalis, N. gonorrhoeae, N. meningitidis, and N. lactamica respectively.

Color Atlas of Medical Bacteriology By Luis M. De la Maza

In a study published in an article titled: "Evaluation of the BactiCard Neisseria for identification of pathogenic Neisseria species and Moraxella catarrhalis”, the BactiCard Neisseria identified 100% of 254 Neisseria gonorrhoeae, 100% of 125 Neisseria meningitidis, 53 (98.2%) of 54 Neisseria lactamica, and 123 (98.4%) of 125 Moraxella catarrhalis isolates. 

 

Sunday, July 3, 2011

Traveler's Diarrhea



We have discussed in class this past week the organisms in the GI tract. One disease in particular is very intriguing and important for me that I wanted to share more information  about it with my colleagues, Travelers' diarrhea (TD).
Travelers' diarrhea is the most common illness that affects travelers worldwide. Each year about 10 million travelers develop diarrhea. The onset of TD usually occurs within the first week of travel but may occur at any time while traveling, and even after returning home. High-risk destinations are the developing countries of Latin America, Africa, the Middle East, and Asia. High-risk populations include young adults, immunosuppressed patients, persons with inflammatory-bowel disease or diabetes, and persons taking H-2 blockers or antacids are at risk at contracting TD. The primary source of infection is ingestion of food or water, contaminated with feces.

Most TD cases begin abruptly. The illness usually results in increased frequency, volume, and weight of stool, along with nausea, vomiting, diarrhea, abdominal cramping, bloating, fever, urgency, and malaise.
The most common isolated organism in countries surveyed has been enterotoxigenic Escherichia coli (ETEC), which secretes heat-labile enterotoxin and heat-stable enterotoxin, that cause its toxigenic effects. As we all know, E. coli is a Gram-negative rod commonly found in the lower intestine of warm-blooded organisms, and is mainly transferred through feces with contamination.  The regular presence of E. coli in the human intestine and feces has led to tracking the bacterium in nature as an indicator of fecal pollution and water contamination.  
http://www.medscape.com/viewarticle/502559

Studies have shown that the use of bismuth subsalicylate(Pepto Bismol), taken as either 2 tablets 4 times daily or 2 fluid ounces 4 times daily reduces the incidence of travelers' diarrhea.

Reference:
www.cdc.gov
 http://www.textbookofbacteriology.net/e.coli.html
http://www.cdc.gov/ncidod/dbmd/diseaseinfo/etec_g.htm

Sunday, June 26, 2011

Lab Week 3

This week's lab was very interesting. I don't know about everyone else, but i found it extremely helpful to look at throat and sputum cultures the way we did; this was probably the first time I had to look and differentiate between 2 different, yet very similar colonies on the same culture.
The main problem that I faced while differentiating the 2 colonies is that they looked very much alike, they both grew on sheep blood agar only, and did not grow on MAC (which means they were both gram positives). The main difference I had is that one of them was beta-hemolytic; however, that was not of much help in the beginning, because the other organism that was not beta hemolytic only grew in limited spaces on the agar, and were very close to the first colony and I rarely had independent colonies that were not intertwined with the first ones. I really hope to have more specimens like these, because I know that it is going to be even more complicated when we graduate and have to figure all this out by ourselves.
My plate looked a lot like the picture attached 

http://medinfo.ufl.edu/year2/mmid/labimage/case3_bc.jpg

The first colonies were beta-hemolytic, PYR negative, PathoDx grouping showed clumping for group c antigen. 
The second colonies showed a gram positive cocci in clusters and staphaurex was negative. 
I am actually not going to list what these organisms are, and I will post it later on this week, hoping that someone might guess what it could be.




Studying tips

http://www.cse.buffalo.edu/~rapaport/howtostudy.html#examstudy

Does this sound familiar? Since we had a test this past week, and did not really cover a lot of material, i wanted to do something a little different and give some studying tips that might be helpful.  I know that most of us have too many homework and studying to do, but organization is the main key to success and doing better.
http://www.cse.buffalo.edu/~rapaport/howtostudy.html#examstudy

I have looked over many references, and basically studying for a test can be summed in those few points:
  1. Manage your time: Begin studying about 1 week before the exam. Spend at least an hour each night (or day) studying for the exam . Try to spend the entire night (and/or day) before the exam studying for it.
  2. How not to study: re-reading your textbook has "little or no benefit" when you are studying for a test. One method of studying that is better than passive re-reading is the "read-recite-review" ("3R") method: "Read the text, set the text aside and recite out loud all that [you can] remember, and then read the text a second time" (McDaniel et al. 2009).
  3. Make a study outline
  4. Write sample essays & do sample problems
  5. Make "flash cards"
  6. Stop studying when you feel confident: when you get to the point that you feel confident and ready for whatever will be on the exam and actually eager to see the exam to find out if you guessed its contents correctly, then you know that you are ready and you should be able to get some rest and sleep in order to be ready. 
Other tips have proven to be extremely powerful guides for organizing, thinking, studying, and learning in college.
Study Space
Your study space should be as quiet and comfortable as possible. Avoid studying in noisy places such as cafeterias, recreation rooms, or lounges.
Tip: When studying, keep a waste basket handy.
Tip: Have everything needed for studying handy beforehand. Don't waste valuable time looking for books, notes, of other information. After you have assembled the items you need, put them where you can reach them easily.
Study Habits
Tip: Begin studying no less than 30-90 minutes after a meal.
Tip: Never study within 30 minutes of going to sleep.
Tip: Prioritize! Make a list of what you intend to study, prioritize the list, and stick to it!
Tip: If possible, study no more than 30-40 minutes at a stretch.
Tip: Take study breaks away from your desk or wherever you are studying. 


references:
http://www.cse.buffalo.edu/~rapaport/howtostudy.html#examstudy
http://www.teachervision.fen.com/study-skills/teaching-methods/6390.html?detoured=1
http://www.adprima.com/studyout.htm

Friday, June 17, 2011

Listeriosis

During our lab this week, i have come across an organism that is a serious concern in public health.  Therefore I did some research on Listeria monocytogenes and listeriosis.
Listeriosis is usually caused by eating food contaminated with Listeria monocytogenes, and is an important public health problem in the United States according to the CDC website. It primarily affects older adults, pregnant women, newborns, and the immunodeficient patients.
Listeria is killed by pasteurization and cooking; however, in some ready-to-eat foods, contamination may occur after factory cooking but before packaging. Unlike most bacteria, Listeria bacteria can grow and multiply in the refrigerator. (Does anyone still want to eat that rare meat at the restaurant?)
Pregnant women have to be particularly careful, because other than the fact that their immune system is compromised, babies can be born with listeriosis if their mothers eat contaminated food during pregnancy. 
I have also found this interesting article from the CDC website titled:
Outbreak of Listeria monocytogenes Infections Associated with Pasteurized Milk from a Local Dairy --- Massachusetts, 2007 and you can find it at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5740a1.htm. This article or incidence, along with the previous article that I posted last week, just points out the seriousness or severity of risk of contamination to the general public.



Respiratory tract infections

We have discussed in class this week upper and lower respiratory tracts, and there is a lot of information involved while studying for those diseases. I have found some tables and pictures that some of us might find useful.

A fun fact about upper respiratory tract infections is that they are the most common infectious causing illness in the general population and they are the leading reasons for people missing work or school, and the leading acute diagnosis in the office setting.

Disease Location Disease Group of Pathogen Comments
Upper respiratory tract
Nasal passages Common cold Viruses Most common cause rhinovirus
Nasal sinuses Rhinosinusitis Viruses
Bacteria
Viruses are most common cause of rhinosinusitis
Pharynx Pharyngitis Viruses  Streptococcus pyogenes and Corynebacterium diphtheriae Viruses cause 90% of these infections
Respiratory airways
Epiglottis Epiglottitis Bacteria Usually Haemophilus influenzae type b
Trachea and bronchi Bronchitis, tracheobronchitis, croup, laryngitis Viruses Usually caused by viruses
Bronchioles Bronchiolitis Viruses Most common cause is respiratory syncytial virus
Lower respiratory tract
Alveoli and alveolar sacs Pneumonia Bacteria Most common cause in adults is Streptococcus pneumoniae

And this schematic might simplify some of the pathogens that do cause the various diseases.



 






http://www.atsu.edu/faculty/chamberlain/Website/lectures/lecture/introurt.htm

Sunday, June 12, 2011

9 Dead After IV Infections at 6 Ala. Hospitals


We spoke in class about the importance of following the correct procedures to avoid contamination of samples, or sterile solutions. This article is a perfect example of what could happen if an unwanted organism is present, and how it could affect our patients, and their lives.

This article is from the following link:


Also for a video about the same issue, please follow this link from CNN:

9 Dead After IV Infections at 6 Ala. Hospitals

Mar 29, 2011 – 9:11 PM
Text Size
Anna McFall
AP
MONTGOMERY, Ala. -- Nine Alabama hospital patients who were treated with intravenous feeding bags contaminated with bacteria have died and the maker has pulled the product off the market, state health officials said Tuesday.

Ten others who got the nutrient treatments that are delivered directly from the plastic bags into the bloodstream through IV tubes also were sickened by the outbreak of serratia marcescens bacteria, health officials said. All the patients were critically ill before receiving the IVs and officials have not definitively tied the deaths to the outbreak at six hospitals, State Health Officer Donald Williamson said.

"There is nothing to suggest the deaths were directly related to the bacterial infection," said Williamson who declined to give details on the patients including their ages and illnesses.
intravenous, solution, iv, outbreak, alabama hospital,
Christopher Furlong, Getty Images
State officials confirmed on Tuesday that nine hospital patients who were treated with contaminated intravenous feeding bags have died, and the maker has pulled the product off the market.

On March 16, two hospitals reported increased cases of serratia marcescens to the Alabama Department of Public Health. Officials linked the infection to TPN, a common nutritional supplement delivered through IVs.

A single pharmacy, Birmingham-based Meds IV, made the bags. Williamson said the company has notified its customers of the contamination, has discontinued production and was being very cooperative.

"We wouldn't be nearly as far along as we are without them," said Williamson.

Calls to Meds IV and its owner seeking comment were not returned.

Meds IV is registered to Edward Cingoranelli, who appears to have been involved in at least three other medical supply companies, according to the Alabama Secretary of State's office. Meds IV was incorporated two weeks after one of the other firms.

When Select Specialty Hospital in Birmingham learned one of its suppliers may have distributed bags containing the bacteria, it started investigating and stopped using Meds IV products, said the hospital's chief executive officer. Other hospitals also immediately stopped using the products.

"We are committed to high-quality patient care and are fully cooperating with government officials in their ongoing investigation of the supplier," said Jeffrey Denney.

Hospitals have very strict infection control for TPN. The supplement compound of several different nutrients, including electrolytes, is delivered daily in bags that are pre-mixed, not done in the hospital. The supplement is administered into a central line intravenously, going directly into the patients' blood stream. Patients are monitored carefully for symptoms of septic shock.

Serratia marcescens bacteria grow in moist areas and can settle in hospital patients' respiratory and urinary tracts. The bacteria is common and easily treatable if detected early. Patients with serratia sepsis may have fever, chills, shock, and respiratory distress.

http://www.aolnews.com/2011/03/29/9-dead-after-iv-infections-at-6-ala-hospitals/?icid=maing-grid7|main5|dl1|sec3

S. dysgalactiae subsp. equisimilis

In my lab results, i have encountered a patient diagnosed with endocarditis due to an infection with S. dysgalactiae subsp. equisimilis, an organism that many of us probably don't know a lot about, so i thought i could just elaborate a little bit about it and add some information about it. 
S. dysgalactiae subsp. Equisimilis (SDSE) is a sub-specie of Group G Streptococcus (GGS) species, which were first isolated in patients with puerperal sepsis in 1935.  GGS are known to be commensals and pathogens in domestic animals. In humans, they may colonize the pharynx, skin, gastrointestinal and female genital tract. It has been increasingly reported in human infections such as pharyngitis, cellulitis, meningitis, endocarditis, and sepsis. S. dysgalactiae subsp. equisimilis is the most common species of GGS that is β-hemolytic on sheep blood agar. 
The pathogenicity of S. dysgalactiae subsp. equisimilis has a wide spectrum of disease similar to that caused by Streptococcus pyogenes. Invasive infections with SDSE comprise arthritis, osteomyelitis, pleuropulmonary infections, peritonitis, intra-abdominal and epidural abscesses, meningitis, endocarditis, puerperal septicemia, neonatal infections, necrotizing fascitis, myositis, and streptococcal toxic-like syndrome. The invasive infections caused by SDSE has been found to be due to a rare mutation of the emm gene, which encodes for the M protein, which is a major virulence factor is SDSE (also present in S. pyogenes).
SDSE is susceptible to penicillin and other β-lactam agents, and penicillin is considered the drug of choice. The addition of an aminoglycoside to the cell wall-active agent is granted in serious infections. Also the Quinolone drugs have shown to have very good coverage for the eradication of the organism and treatment of invasive infections.
In conclusion, SDSE has many times been overlooked as a potential for invasive infections, and physicians and microbiologists are learning to look for this organism more, in order to provide the patient with optimized antimicrobial regimen.

Sunday, June 5, 2011

Welcome To My Microbiology Blog!

Welcome to Taha's blog.
This Blog was created to post information, questions, comments and pictures related to Mrs. Linda Jeff's microbiology class, CLS 538. This is a learning experience for all of us, and together we will learn about the organisms and the infections they cause according to the different organ systems.
Your feedback will be appreciated, and hope that I will be able to provide some useful information.
See you in class.