This publication was designed by Option Care with you in mind and will serve as your one source for "hot" topics in home infusion today.

Option Care is The Best Option@...for home infusion therapies and specialty pharmaceuticals.

Multidrug-resistant Microorganisms

Microorganisms playa role in our everyday lives. The human body is home to billions of bacteria. Under ordinary circumstances these bacteria are not harmful and are often beneficial. The intestines are inhabited by billions of bacteria that digest nutrients and ward oft food-borne pathogens such as Salmonella and Campylobacter. Many bacteria live on our skin. It is when bacteria enter a normally sterile environment, such as urine, that infections occur. When antibiotics are taken the infecting causing bacteria is killed, but so are the normal and beneficial bacteria.

Almost 25 million pounds of antibiotics produced by U.S. pharmaceutical companies are used in animal feed to enhance growth when a multidrug-resistant microorganism develops in an animal it is passed to humans through ingestion of animal products.

Despite advances in therapy and education to not over use antibiotics microorganisms that are resistant to conventional therapy continue to be a threat to patients. The multidrug-resistan1 organisms include:

• Vancomycin-resistant enterococci (VRE)
• Methicillin-resistent Staphylococcus aureus (MRSA)
• Penicillin-resistant S. aureus (VRSA)
• Extended-spectrum beta lactamase producing organisms (ESBLs)

Antibiotics have improved the quality of life and increased life expectancy. There also has been a down side. A false sense 01 security has been established. These multidrug resistant Gram-positive and Gram-negative bacteria are the direct result 01 extensive and sometimes inappropriate use of antibiotics in humans and animals.

In 1996 VRE was found on the hands of health care workers ever after washing their hands. To kill VRE on the skin an antiseptic soap that contains chlorhexadine must be used. The most common cause for VRE is Enterococcus faecalis and Enterococcus faecium. Both species are resistant to cephlosporins and increasingly resistant to aminoglycosoids, the may respond to linezolid (Zyvox@). The infusion dosing of this drug is 600mg ever) 12 hours for 14-28 days, infused over 30-120 minutes and can be given to pediatrics and dosed at 10mg/kg every 8 hours for 14-2~ days under age 11. By sending the patient home on this medication there can be a tremendous decrease in hospital stay as well as removal of the patient from an environment where additional exposure to infection is possible.

By 1950 60% of all hospital acquired S. aureus were resistant to penicillin because random strains had developed an enzyme (beta. lactamase) that could destroy the penicillin molecule's beta-lactarm ring. making the drug ineffective. To combat the resistance new classes of semisynthetic medications were developed. In 1961 a methicillin resistant strain of S aureus appeared in Europe and in 1968 appeared in the United States. The U.S. strains were resistant to aminoglycosides, erythromycin, tetracycline and clindamycin. Vancomycin is often used to treat MRSA. Due to the emergence of VRSA, linezolid, quinupristin/dalfopristin (Synercid@), or daptomycin (Cubicin@) may be more appropriate. Dosing of Synercid@ is 7.5 mg/kg IV every 8 hours, while Cubicin@

S. pneumoniae is usually associated with community acquired pneumonia (CAP) in adults and acute otitis media (AOM) in children it can also cause meningitis, sinusitis and bacterial bronchitis in any patient of any age. In 1990, penicillin (or ampicillin) was the drug of choice for CAP caused by S. pneumoniae. Today 44% of all cases in the United States have reduced susceptibility to penicillin. In some areas of the country, many penicillin-resistant strains are also multidrug resistant. The drugs of choice are ceftriaxone plus a floroquinolone (Cipro@, Levaquin@). If these drugs fail, then Vancomycin plus azithromycin may be used. (MJH)

Reference: Schef B. Multi-resistant microorganisms Still making waves. Nursing 2003. Vol 33. No 11

West Nile Virus Update

West Nile Virus is endemic throughout much of the United States. In 2003, 2700 confirmed cases occurred with 164 deaths. Older persons are at substantially increased risk for severe WNV disease. Symptoms include profound muscle weakness, often with acute flaccid paralysis and poliomyelitis-like syndrome. A follow-up study was done on a cohort of New York City patients (40) infected in 1999 are recovering. The purpose of the study was to describe outcomes in the 18 months since acute illness and determine whether the severity, age, and underlying illness affected recovery.

WNV infection can result in a protracted convalescent period with long-term physical, cognitive, and functional impairments lasting >18 months after acute illness. Approximately 40% of patients hospitalized in 1999 did not return to their own homes immediately after discharge, and 47% of patients required physical therapy after hospitalization. Comparing the symptoms before illness with those at 12 months after onset, physical, functional, and cognitive symptoms persisted. Approximately 37% of patients achieved full recovery by 12 months. Younger age «65 years) was the only significant predictor of achieving a full recovery.

Regardless of acute clinical symptoms, patients continued to report difficulty walking, muscle weakness, fatigue, and insomnia, with >40% reporting a combination of these difficulties, and 30% continued to report persistence of memory loss, confusion, depression, and irritability at 18 months after acute illness. Eighteen months after illness, 30% of case-patients reported needing assistance with activities of daily living, mostly those requiring increased strength. Generally functionality improved over 6-12 months then reached a plateau during the 12-18 month period after onset.

Treatment is supportive, often involving hospitalization, intravenous fluids, respiratory support, and prevention of secondary infections for patients with severe disease.

• Ribavirin in high doses and interferon alpha-2b were found to have some activity against WNV in vitro, but no controlled studies have been done using these or other medications, including steroids, antiseizure drugs, or osmotic agents.

WNV continues to establish itself as a national public health concern. Local governments in affected areas need to institute widespread public health measures to protect against WNV transmission and for persons, particularly those above age 65, to take precautions to avoid exposure and reduce mosquito breeding sites on their properties. (SP)

CDC Emerging Infectious Diseases Long-term Prognosis for Clinical West Nile Virus Infection. Ahead of Print Vol 10, No. 8 August 2004

The Best Option@...for home infusion therapies and specialty pharmaceuticals.

HOME - about us - services  - resources/links - clinicians, case management, referral information - clinical pearls newsletter

©2004 Option Care, Inc. All rights reserved.
The articles herein are provided for general information and are not intended to provide specific advice or recommendations for any reader.