Case Study Pathogenic Bacteriology 2009 Case #13 Team Members: Jae Kim, Roubina Tatavosian, James Muro

Case Summary The patient is a 40 year-old male with multisystem failure secondary to bilaterial pneumonia. Complained to physician three days before transfer to a hospital via helicopter of fevers, malaise, and vague respiratory symptoms. He was given amantadine for suspected influenza. The patients condition became progressively worse, with shortness of breath a fever to 40.5 0C, and he was admitted to an outside hospital 24 h prior to transfer.

Key Information Pointing to Diagnosis A laboratory examination revealed liver and renal functions. Therapy with Timentin and trimethoprim-sulfamethoxazole was begun. On admission, he underwent a bronchoscopic examination which revealed mildly inflamed airways containing thin, watery secretions.

The Diagnosis for Case #13 A Gram stain of bronchial washings was obtained. Bronchial washings is a procedure in which isotonic saline is instilled through a bronchioscope and fluid containing cells, microorganisms, or other material from the upper airways --- trachea, bronchi, bronchioles, is aspirated into a trap; the material is then centralized to concentrate the cells, stained, and examined by microscopy or cultured if infection is suspected.

Diagnosis for Case #13 The genus Klebsiella belongs to the tribe Klebsiellae, a member of the family Enterobacteriaceae. Klebsiella pneumonia is a Gram-negative, non-motile, encapsulated, lactose fermenting, facultative anaerobic, rod shaped bacterium found in the normal flora of the mouth, skin, and intestines. It is the most important member of the Klebsiella genus of Enterobacteriaceae; it is closely related to K. oxytoca from which it is distinguished by being indole negative.

Klebsiella pneumoniae Scientific classification Kingdom: Bacteria Phylum: Protobacteria Class: Gamma Proteobacteria Order: Enterobacteriales Family: Enterobacteriaceae Genus: Klebsiella Species: K. pneumoniae Binomial Names: Klebsiella pneumoniae

Classification, Gram Stain Results, and Microscopic Appearance of Klebsiella pneumoniae K. Pneumoniae is a community-acquired bacterial pneumoniae but S. pneumoniae is the most common cause of bacterial pneumoniae.

Diseases and Pathogenesis of Disease Caused by Klebsiella pneumoniae K. pneumoniae has been a recognized pulmonary pathogen since its discovery more than 100 years ago. A striking clinical finding concerning a new manifestation of community-acquired K. pneumoniae infections has been documented. An unusual presentation of K. pneumoniae infection, primary bacteremic liver abscess, has been described by numerous investigators in Asia. A third striking clinical observation is the preponderance of K. pneumoniae as a community-acquired bacterial meningitis in adults in Taiwan, even in the absence of liver abscess or other sites of infection..

Diagnosis/Isolation/Identification/of Klebsiella pneumoniae NF of GI tract, but potential pathogen in other areas TSI A/A+gas LIA K/K Urea + Citrate + MR-, VP+ Motility – Has both O and K antigens EMB – blue colonies on black agar

Therapy, Prevention and Prognosis of Patient Infected with Klebsiella pneumoniae Virulence factors Capsule Adesions Iron capturing ability Clinical Significance --Causes pneumoniae, mostly in immunocompromised hosts --Permanent lung damage is a frequent occurrence (rare in other types of bacteria pneumonia) --A major cause of nosocomial infections as septicemia and meningitis

Therapy, Prevention and Prognosis of Patient Infected with K Therapy, Prevention and Prognosis of Patient Infected with K. pneumoniae Antibiotic Selection Cephalosporins Carbapenems Aminoglycosides Quinolones Trimethoprim/sulfamethoxazole

Deterrence/Prevention Follow hospital protocol for infection control to limit spread of infection and resistance Proper hand washing is crucial for prevent transmission from patient to patient via medical personnel Contaminated nebulizers are a major source of hospital-acquired infection; this source has been eliminated through the use of disposable devices

Primary Research Article Struve, Carson, et al, 2008, Characterization of Klebsiella pneumoniae Type 1 Fimbriae by Detection of Phase Variation during Colonization and Infection and Impact on Virulence, Infection and Immunity, vol: 4055-4065. Experimental setup used bacterial strains and mouse models. What did they find: They found that most clinical isolates produce vast amounts of capsular polysaccharide covering the bacterial surface. The capsule protects the bacteria against opsonization and phagocytosis, and the significance of the capsule in K. pneumoniae virulence has been demonstrated in several studies This article relates and supports my case that K. pneumoniae is the second most common agent of gram-negative sepsis as epidemiological studies have revealed that the first step of K. pneumoniae infections is the colonization of the patient’s gastrointestinal tract.

Take Home Message K. pneumoniae typically affects middle-aged and older men with debilitating diseases such as alcoholism, diabetes, or chronic bronchopulmonary disease Typical symptoms include pneumonia, bacteremia, thrombophlebitis, urinary tract infection, cholecystitis, diarrhea, upper respiratory tract infections, wound infections, osteomyelitis, and meningitis Diagnostics tests include McKonkey agar, Indole, Eosin-methylene Blue Agar, PCR. Therapy is based on a third generation cephalosporins and aminoglycosides Prognosis for K. pneumoniae has a 50% mortality rate, even with adequate therapy. The prognosis is worse in patients with alcoholism and bacteremia

Take Home Message Preventive strategies and early diagnosis and treatment help to reduce morbidity. Transmission is via air droplets. The threat is serious in hospitals and for individuals that are diabetic and alcoholics.

References Mahon, Connie R., and et al. (2007). Textbook of Diagnostic Microbiology (3rd ed.). Missouri: Saunders ElSevier, Inc. Patterson, David L., and et al. (2002). Community-Acquired Klebsiella pneumoniae Bacteremia: Global Difference in Clinical Patterns. CDC, 8, 1-15. Struve, Carsten, Bojer, M., & Krogfelt, K. (2008). Characterization of Klebsiella pneumoniae Type I Fimbriae by Detection of Phase Variation during Colonization and Infection and Impact on Virulence. Infection and Immunity, 76, 4055-4065. Umeh, Oblaamiwe. (2006). Klebsiella Infections: Treatment & Medication [Electronic version]. eMedicine 7(5), 1-5. Retrieved March 10, 2009, from http://emedicine.medscape.com/article/219907-treatment.