Influenza Virus

Influenza, caused by highly infectious RNA viruses of the orthomyxovirus family, is a major cause of morbidity and mortality among patients with chronic diseases and those over the age of 65 yr. Influenza A viruses are classified into subtypes based on two surface antigens hemagglutinin (H) and neuraminidase (N). Changes in the H or N antigen account for the epidemiologic success of these viruses. Antigenic shift is the emergence of influenza A viruses with novel H or N antigens that occurs...

References

Resistant pneumococci protecting patients through judicious use of antibiotics. Am Fam phys 1997 55 1647-1654. 2. Arason VA, Kristinsson KG, Sigurdsson JA, Stefansdottir G, Molstad S, Gudmundsson S. Do antimicrobials increase the carriage of penicillin resistant pneumococci in children Cross sectional prevalence study. Br Med J 1996 313 387-391. 3. Austin DJ, Kristinsson KG, Anderson RM. The relationship between the volume of antimicrobial consumption in human communities...

Etiology

The most commonly encountered pathogens in bacterial IE are streptococci, staphy-lococci, and enterococci. The HACEK organisms (Hemophilus spp., Actinobacter spp., Cardiobacterium spp., Eikenella spp., and Kingella spp.) and Gram-negative bacteria (Klebsiella spp., Pseudomonas spp., and Esherichica spp.) are less frequent offenders. Other rare but important pathogens include Rickettsia spp., Bartonella spp., Legionella spp., Brucella spp., Neisseria spp., Mycobacterium spp., fungi, and Nocardia...

Acute Sinusitis

Acute sinusitis has considerable overlap in its constellation of signs and symptoms with URIs. One half to two thirds of patients with sinus symptoms seen in primary care are unlikely to have sinusitis (35). In 300 patients who presented with a URI, 19 had radiographic evidence of maxillary sinusitis, but had no symptoms of sinus infection (30). URIs are often precursors of sinusitis and at some point symptoms from each condition may overlap. Sinus inflammation from a URI without bacterial...

Acute Bronchitis

Acute bronchitis is an inflammatory condition of the tracheobronchial tree usually associated with a generalized respiratory infection. Cough begins early in the course of the illness and is the most prominent feature of the condition. An initially dry cough may later result in sputum production which characteristically changes from clear to discolored in the later stages of the illness. The cough may last for a significant time. Although the duration of the condition is variable, one study...

Infections Of The Intestine Small And Large

Infections in the small and large intestine can present in a number of ways, making the diagnosis difficult. Symptoms may include malaise, fever, headache, and abdominal pain. Diarrhea, however, is the most widely recognized marker of intestinal infection including both small bowel and colon. Classification of diarrhea is usually based on symptom duration and may be acute (lasting < 3 wk) or chronic (lasting > 3 wk). Diarrhea can also be classified by pathophysiological type, including...

Cystitis

Clinical Description, Epidemiology, and Etiology Cystitis connotes infection limited to the urinary bladder. It is a clinical syndrome characterized by irritative voiding symptoms e.g., dysuria, frequency, and urgency and bacteriuria pyuria, in the absence of flank pain or fever to suggest renal or systemic involvement 1 . In children too young to report voiding symptoms, cystitis All practice suggestions are followed by quality of evidence assessments A supported by randomized trial,...

Types Of Infections

Candida spp. can cause superficial mucocutaneous or deep infections 17 . Candi-dal infections are extremely common, ranging from oral thrush to disseminated disease. Thrush most often occurs in patients on steroids or chronic antibiotics and in immunocompromised patients, especially those with HIV infection. In addition to the classic creamy white coating of the tongue and oral mucosa, oral candidiasis can present as an atrophic form, as angular cheilitis, or as Candida leukoplakia. In...

Acute Otitis Media

Acute otitis media is one of the most common pediatric conditions seen in primary care. In 1990 there were 12.8 million episodes of acute otitis media in children lt 5 yr old in the United States, with total estimated costs of 3.5 billion including 240 million spent on antibiotics 49 . Despite the extensive clinical experience in the management of otitis media, there is no consensus regarding which antibiotics are most appropriate for initial or recurrent therapy, the optimal duration of...

Hepatitis B

Hepatitis B is produced by a DNA virus classified as a hepadnavirus type 1 40-42 . There are multiple serotypes. More than 300 million people suffer from chronic hepatitis B virus HBV infection more than 75 of affected individuals live in Asia or are of Asian origin. The usual incubation period is 2-3 mo but may be as short as 45 d and as long as 6 mo. The frequency of clinical illness with jaundice is different at different ages. Fewer than 10 of the patients acquiring infection when younger...

Folliculitisfurunclescarbuncles

Folliculitis is an infection of the pilosebaceous unit and involves only minor inflammation of an individual hair follicle. This infection is associated with minimal pain and surrounding erythema. Gram-negative folliculitis most often develops as a superinfection in people who have undergone prolonged oral antibiotic therapy. It is characterized by pustules in the area of the nose. The pathogens in the superficial form of this infection are usually Klebsiella or Enterobacter species. A deep...

Respiratory Syncytial Virus

Respiratory syncytial virus RSV is highly infectious and easily transmitted from person to person by close contact. The primary modes of transmission include direct contact with large droplets of secretions small particle aerosol is not a significant mode of transmission and self-inoculation of eyes and nose by hands made infectious by touching contaminated objects. For example, RSV can be isolated from countertops more than 6 h after contact with an infected source such as nasal secretions....

Infections In The Solid Organ Transplant Recipient

Clinical Description and Epidemiology The course of solid organ transplant recipients is often complicated by infectious processes, owing to defects in both cellular and humoral immunity. However in the past several decades, improvements in graft and patient survival and a decline in infection-related mortality have been observed, probably related to better regulation of chronic immunosuppressive therapy, better selection of transplant candidates, improved antimicrobial prophylaxis, and...

Esophageal Infections

Esophageal infections have increased in frequency over the last decade, in part as a result of the growing numbers of patients with acquired immunodeficiency syndrome AIDS and organ transplantation requiring immunosuppressive therapy. Patients with esophageal infections may be asymptomatic however they more commonly present with symptoms of dysphagia difficulty in swallowing or odynophagia painful swallowing . Rarely does esophageal infection progress to more serious complications such as...

Impetigo

Impetigo is a skin infection commonly found in children of preschool age, but may also occur in adults. Impetigo accounts for about 10 of all pediatric skin problems 4 . It typically spreads from one part of the body to another through scratching and is a highly communicable disease. Impetigo has two classic forms nonbullous and bullous. The nonbullous form is more common and accounts for approx 70 of cases. This form is commonly associated with a honey-colored crusted discharge. As intact skin...

Diseases Characterized By Urethritis And Cervicitis

Neisseria gonorrhoeae and Chlamydia trachomatis cause the majority of urethritis and cervicitis. The etiology of most nongonococcal, nonchlamydial urethritis is unknown. Other agents that may cause urethritis include Trichomonas vaginalis and Herpes simplex. Ureaplasma urealyticum and possibly Mycoplasma genitalium also have been implicated as causes of urethritis. Urethritis refers to inflammation of the urethra in men or women and is manifested by dysuria, pyuria, or discharge. Discharge may...

Enterococcus

Members of the genus Enterococcus were formerly classified with the Lancefield group D streptococci. Growth at extremes of temperature, salinity, and alkalinity as well as hydrolysis of esculin in the presence of bile characterize these organisms. More recently genetic techniques have been used to clarify the taxonomy. These facultatively anaerobic Gram-positive cocci are usually found in the gastrointestinal and biliary tracts, vagina, and male urethra. Historically not considered pathogenic...

Fungal

Clinical Description, Epidemiology, and Etiology Fungal UTI, an increasingly frequent problem, is generally limited to hosts with an obvious predisposing factor such as diabetes mellitus, antibiotic therapy, and or indwelling bladder catheter use 53 . Candida species predominate overwhelmingly as the causative agents, with Aspergillus and other fungi only rarely causing UTI, and then only in profoundly immunocompromised hosts. The great majority of fungal UTIs are asymptomatic and, like...

Respiratory Syncytial Virus Infection Control Guidelines

General control measures to prevent nosocomial RSV transmission Educate hospital staff about RSV epidemiology, modes of transmission, and means of prevention. Use contact and droplet isolation for RSV-positive patients including gloves and gown. Maintain good handwashing procedures following any contact with RSV-infected patients or fomites, even if gloves are used. Limit visitors. Do not allow visitors with who have symptoms of respiratory infection to visit uninfected pediatric,...

Subacute Or Chronic Meningitis

Subacute or chronic meningitis is characterized by a gradual onset, often without any predisposing factor. These syndromes run their course over weeks, months or years. The clinical signs include headache, fever, stiff neck, and altered consciousness. Lower cranial nerve palsies may accompany basilar meningitis. Of the treatable conditions, crytococcosis and syphilis can be easily diagnosed on the basis of serology and antigen detection. Lyme disease Borrelia burgdorferi with nervous system...

Diseases Characterized By Vaginal Discharge

Vaginitis and vaginal discharge are common complaints prompting women to visit their health care providers. The differential diagnosis is extensive and should include physiologic discharge, chemical or irritant vaginitis, atrophic vaginitis, and vaginitis due to the infectious agents discussed in the following sections. Many over-the-counter products, such as topical antifungals, are widely available and allow women to self treat, often inappropriately. This makes diagnosis even more difficult...

Varicellazoster Virus

Like the herpes simplex viruses, varicella-zoster virus VZV is an enveloped, dou-ble-standed, DNA virus of the herpesvirus family. VZV causes two distinct clinical syndromes. Primary exposure to VZV results in varicella chickenpox , a usually benign, highly contagious infection of children. Reactivation of latent VZV results in herpes zoster shingles , an illness most commonly seen in adults over the age of 45 yr. VZV is spread from person to person by direct contact, as an aerosol from skin...

Alice C Thornton David Adkins and Janet Arno Introduction

Sexually transmitted diseases STDs are a complex set of syndromes involving more than 25 pathogens acquired through sexual activity. A majority of the 12 million Americans infected with STDs each year are not treated in a public STD clinic 1 . This emphasizes the need for all clinicians to be aware of and provide management for STDs according to the Center for Disease Controls' CDC STD Treatment Guidelines 2 . In an era of emerging antimicrobial resistance and incurable viral STDs, prevention...

Hepatitis C

Hepatitis C is caused by an RNA virus that has many features similar to the fla-viviruses 35 39 . Hepatitis C represented 16 of the cases of acute hepatitis in the sentinel study from the CDC from 1982 to 1993. Despite this, hepatitis C represents more than half of all the cases of chronic viral hepatitis in the United States. The incubation of the infection is from 2 to 26 wk. Clinical illness occurs in 30-40 of the patients, but only 20-30 of all the patients will develop jaundice. There are...

Treatment

Antifungal agents are much more limited in number than are antibacterial drugs 22-24 . Unfortunately, many of the available agents have significant cost and toxicity. Currently available drugs for the treatment of fungal infections are amphotericin B and the newer liposomal forms of amphotericin, flucytosine, and the azole drugs 25,26 . The polyene amphotericin B is the mainstay of therapy for serious fungal infections and remains the most broad-spectrum antifungal agent available. Its broad...

Human Papilloma Virus

Human papilloma virus HPV infections have two important clinical manifestations external genital warts EGWs and squamous intraepithelial lesions 30 . A discussion of these neoplasms is beyond the scope of this chapter but screening and treatment issues can be found elsewhere 2 . The majority of newly acquired HPV infections are asymptomatic. EGWs are diagnosed when visible warts occur in the genital area they can be discrete or coalesce into confluent plaques 30 . The acetowhite test has not...

Herpes Simplex Viruses

Herpes simplex viruses HSV are enveloped double-stranded DNA viruses in the herpesvirus family. HSV I and II have the capacity to invade and replicate in the central nervous system, establish latent infection, and recur in the presence of humoral and cell-mediated immunity. Latent stages of HSV I and II occur as a result of viral entry into sensory nerve endings following primary infection. The virus is then transported to the nuclei of sensory ganglia where, in the majority of patients, it...

Measuring Antibiotic Resistance

Laboratory testing for antibiotic resistance is generally done by using phenotypic assays, although for an increasing number of cases, genotype-based assays can provide rapid information 61,62 . Phenotypic assays are based on in vitro inhibition of growth of a microorganism in the presence of an antibiotic. These assays are used for organisms that can be cultured on artificial media bacteria on agar or broth media and viruses in cell culture. For bacteria, disk diffusion or broth agar dilution...

Factors Promoting Antimicrobial Resistance And Measures To Control Its Spread

Antibiotic exposure is the main factor promoting antibiotic resistance in both populations and individuals, although crowding and other risk factors also contribute selective pressure for resistance and encourage its spread Table 3 8,12,71,72 . We have categorized resistant pathogens as foodborne, hospital-acquired, or community-acquired. While appropriate measures to curb development of resistance have different Three Types of Resistant Pathogens and the Implications for Control Measures...