Group B streptococcal bacteremia in nonpregnant adults at a community teaching hospital.

Chatrchai Watanakunakorn (+)

ABSTRACT

Background. Group B streptococcal bacteremia in nonpregnant adults continues to be a significant infection.

Methods. We reviewed medical records of nonpregnant adult patients with group B streptococcal bacteremia from 1995 to 1999 and compared the findings with data from a similar study in our institution between 1980 and 1984.

Results. There were 36 episodes of group B streptococcal bacteremia. The mean age was 70 years. Most of the cases (94%) were community-acquired. The most common underlying disease was diabetes mellitus (49%). The most common sources of group B streptococcal bacteremia were pneumonia and soft tissue infections. The overall mortality rate was 16.7%.

Conclusions. Group B streptococcal bacteremia is still found mainly in the elderly, with significant underlying disease, particularly diabetes mellitus. The spectrum of infection has included lymphadenitis, ascending cholangitis, mastitis, prostatitis, and toxic shock syndrome. The mortality has decreased significantly during the past 15 years (16.7% vs 67.9%).

GROUP B streptococcal bacteremia in nonpregnant adults was not well appreciated before the 1980s. (1,2) We published a study in 1985, (3) and other articles have been published since that time. (3-17) For the past 25 years, the character of group B streptococcal bacteremia in nonpregnant adults has changed in some aspects. Previous studies (before 1990), both hospital-based and population-based, have reported a high mortality from this infection. (3-6,8,13) Nosocomial acquisition of group B streptococcal bacteremia has been reported. (3-6, 8-11,16) The spectrum of infection has included pneumonia, soft tissue infection, urinary tract infection, septic arthritis, osteomyelitis, endocarditis, and meningitis. In this report, we describe the clinical findings of nonpregnant adult patients with group B streptococcal bacteremia in the late 1990s (1995 to 1999) and compare these with findings in the earlier series (1980 to 1984) from our institution, as well as with findings in other published reports.

MATERIALS AND METHODS

St. Elizabeth Health Center is a major teaching hospital of the Northeastern Ohio Universities College of Medicine. All patients from whom group B streptococcus was isolated from blood culture specimens between January 1995 and December 1999 were identified by using the laboratory logbooks. We reviewed only medical records of nonpregnant adults (more than 18 years of age) who had group B streptococcal bacteremia and were admitted as inpatients. Medical records were reviewed for age, sex, clinical diagnosis, community or nosocomial acquisition of infection, associated medical conditions, concomitant infections, source of group B streptococcal bacteremia, selected clinical laboratory results, treatment, antibiotic susceptibility, and outcome. At this institution, the radiometric blood culture analyzer (BACTEC, Johnson Laboratories, Cockeyville, Md) was used. Group B streptococci-specific antigens were detected by the latex-coagglutination method (Streptocard Acid Latex test, Becton Dickinson Microbiology Syste ms, Becton Dickinson and Co, Sparks, Md). Antibiotic susceptibility tests were done in the clinical microbiologic laboratory by automated methods (Vitek, BioMerieux). Bacteremia was considered community-acquired when the isolate was obtained in outpatients or before 72 hours after admission. A definite source of bacteremia was established by an appropriate clinical description of infection supported by a culture of group B streptococcus from that site. A probable source was determined by a clinical description supported by laboratory data, such as Gram stains of specimens (sputum, joint fluid, cerebrospinal fluid, wound) or imaging studies (chest films, magnetic resonance imaging, bone scan). Toxic shock syndrome was diagnosed by using the criteria for toxic shock syndrome due to group A streptococcus, defined by the Working Group on Severe Streptococcal Infections. (18) Endocarditis was diagnosed by the Duke criteria. (19) We analyzed our data and compared findings from our previous study of group B streptoc occal bacteremia. (3)

RESULTS

From January 1995 to December 1999, 43 patients had blood culture specimens that grew group B streptococcus. There were 44 episodes of group B streptococcal bacteremia, 4 of which occurred in neonates. No group B streptococcal bacteremia was found in parturient women. Medical records were not available in 4 episodes of group B streptococcal bacteremia. Thus, a total of 36 episodes of group B streptococcal bacteremia in 35 nonpregnant adults were available for review.

The clinical findings of these patients were compared with those from the study published in 1985 (Table 1). (3) In the current series, there were 23 men and 12 women. The median age was 70 years. Thirty-four episodes (94.4%) were community-acquired. Of the 2 episodes of hospital-acquired group B streptococcal bacteremia, 1 was associated with pneumonia, and the other was of undetermined primary source. Five patients had polymicrobial bacteremia: 2 patients with pneumonia, 2 patients with osteomyelitis, and 1 patient with cellulitis. In cases of polymicrobial bacteremia, the concomitant blood culture isolates were methicillin-resistant Staphylococcus aureus (2), Haemophilus influenzae (1), Pseudomonas aeruginosa (1), Clostridium species (1), and Corynebacterium species (1).

The definite source of group B streptococcal bacteremia was identified in 15 episodes by growing group B streptococcus in cultures from the sites of infection (sputum, urine, ulcer/wound, paraspinal abscess, and bile). The probable source of group B streptococcal bacteremia was determined in 15 episodes. The sources of bacteremia are listed in Table 2 and are compared with those from earlier series.

The most common sources of group B streptococcal bacteremia were pneumonia and soft tissue infections. The majority of patients with pneumonia were more than 70 years old. The one patient who was younger than 70 was an intravenous drug user. Six of seven episodes of group B streptococcal bacteremic pneumonia were community acquired. Five of seven patients with soft tissue infections had diabetes mellitus. One episode of soft tissue infection was associated with polymicrobial bacteremia in a patient who had rheumatoid arthritis treated with methotrexate and prednisone.

There were 4 episodes of group B streptococcal bacteremia associated with urinary tract infections. All 4 episodes were community acquired, and 3 were in women. Two of these patients had diabetes mellitus. One episode was associated with a kidney stone. There were 3 episodes of group B streptococcal bacteremia associated with septic arthritis (all in patients with prosthetic joints). Although joint fluid culture produced no growth, clinical and laboratory features (fever, joint pain, elevated erythrocyte sedimentation rate, Gram stains of joint fluid, computed tomography of affected joints) were compatible with septic arthritis. Two of these patients had diabetes mellitus. There were 3 cases of osteomyelitis. One of these patients died of infection, 1 had complications (disseminated intravascular coagulopathy, gas gangrene), and 1 had diabetes mellitus. One patient had vertebral osteomyelitis and paraspinal abscess with positive culture for group B streptococcus. This patient had no significant underlying dis eases and no history of previous spinal surgery. There were three cases of probable endocarditis. The diagnosis was based on clinical features, though two-dimentional echocardiography and transesophageal echocardiography showed no lesions compatible with vegetations. Two of these patients were older than 70. One patient, who had diabetes mellitus, had ascending cholangitis (bile grew group B streptococcus). He was found to have extrahepatic obstruction of the distal common bile duct due to a cyst in the head of the pancreas. One patient had group B streptococcal bacteremia and lymphadenitis on two separate occasions (2 months apart). One patient had group B streptococcal bacteremia with mastitis after lumpectomy and radiation for breast cancer. One patient had prostatitis after biopsy for carcinoma of the prostate.

There were two episodes of toxic shock syndrome, both occurring in young women. One was a patient (previously described (12)) with a history of diabetes mellitus and alcoholism, and the source of group B streptococcal bacteremia was not apparent. This patient died. The other had hemochromatosis and urinary tract infection, and she survived.

The overall mortality was 16.7% (6 of 36 episodes) and the attributable mortality was 11.1% (4 of 36 episodes). Four of these patients were more than 70 years old and had multiple predisposing factors such as diabetes mellitus, lung cancer, corticosteroid therapy, chronic renal insufficiency, and congestive heart failure. Severe complications developed in two other patients who were younger than 70 (one of the young women who had toxic shock syndrome, and one patient who had acute renal failure and coagulopathy).

All isolates of group B streptococcus were susceptible to penicillin, ampicillin, cefazolin, and vancomycin (Table 3). Only 85% were susceptible to clindamycin and 62% to erythromycin. Almost all isolates were resistant to tetracycline.

DISCUSSION

Group B streptococcal bacteremia in nonpregnant adults still occurs mainly in the elderly. The median age was 70 in this study and 72 in our previous study, (3) and it ranges from 53 to 68 years in the literature. (3-11, 13-17) Jackson et al (16) reported that nonpregnant adults aged 65 years or older had a 1.8 times greater risk for group B streptococcal infection than those aged less than 65 years. Tyrrell et al (17) also reported that age greater than 65 was a risk factor for group B streptococcal infection. The overall mortality in the present study was 16.7%, which is significantly lower than in our earlier study (67.9%). (3) Other studies have reported steadily declining mortality (Table 4). In the current series, the mortality among patients aged 70 and older was 23.5% (4 of 17 patients), twice that of patients younger than 70 (11.1%, 2 of 18 patients). Higher mortality among older patients has been reported by Verghese et al, (4) Colford et al, (6) and Trivalle et al. (11)

Polymicrobial bacteremia involving group B streptococcus was found in 13.9% of episodes in our series (3) and in less than 20% in other reports. (6-8, 10, 11) Farley et al (15) reported 41% of polymicrobial bacteremia involving group B streptococcus, but their study was population-based. Staphylococcus aureus was associated with group B streptococcus polymicrobial bacteremia in most previous studies. (5,8,9,15,16) Group B streptococcal polymicrobial bacteremia was found mostly in nosocomial infections, as reported in our previous series (3) and by Verghese et al. (4) In contrast, there was no nosocomial polymicrobial bacteremia involving group B streptococcus in the current series.

Nosocomial group B streptococcal bacteremia occurred much less often in this series (6%), in contrast to 46% in our previous series, (3) 70% reported by Verghese et al, (4) and between 17% and 35% reported since 1995. (6,8-11,10) Jackson et al (16) reported nosocomial group B streptococcal bacteremia associated with central venous catheters, diabetes mellitus, congestive heart failure, and seizure disorders.

Cases of group B streptococcal bacteremia associated with diabetes mellitus, cirrhosis, malignancy, long-term corticosteroid therapy, and central nervous system (CNS) disorders (stroke) have been reported. (3-11,16,17) In our study, the most common underlying disease of patients with group B streptococcal bacteremia was diabetes mellitus alone (48.6%).

Pneumonia (19.4%) and soft tissue infections (19.4%) were the most common clinical diagnoses in our study. Pneumonia was also the most common clinical diagnosis in our earlier series and in other hospital-based studies but not the most common clinical diagnosis in population-based studies. (3,4,8,13-10) In the present study, the patients who had pneumonia had CNS disorders, chronic obstructive pulmonary disease, and malignancy. Verghese et al (4) reported pneumonia associated with CNS dysfunction, malignancy, and long-term corticosteroid therapy. Of our 7 patients with pneumonia, 6 (86%) were older than 70 years. Pneumonia also has been reported as the most common clinical diagnosis in group B streptococcal bacteremia in the elderly. (11) Reported mortality from pneumonia with group B streptococcal bacteremia has been high. (3,4,6,16)

Soft tissue infections (including cellulitis, diabetic foot ulcer, and decubitus ulcer) were common sources of group B streptococcal bacteremia in our current series as well as in the earlier series. (3) Soft tissue infections with group B streptococcal bacteremia have been reported as the most common clinical diagnosis in both population-based studies and hospital-based studies. (6,14-16) Diabetes mellitus has been found to be a common underlying condition in patients with group B streptococcal soft tissue infections, being 71.4% in this series and 34.2% and 56% in two other series. (15,17)

Bacteremic group B streptococcal urinary tract infection was found in four patients in the current series and none in our previous study. (3) Urosepsis, a common clinical presentation of group B streptococcal bacteremia, (2,4,11,15,16) was found mostly in female patients with diabetes mellitus in our study. Group B streptococcal urosepsis in men has been found almost always in patients with urinary tract abnormalities such as obstruction, renal calculi, or urinary tract instrumentation." (4,20) Bedridden state is commonly associated with group B streptococcal urinary tract infection in the elderly. (11)

Three patients in the current study and one patient in the previous study (3) had a septic prosthetic joint. Septic arthritis has also been reported in the literature. (6,13,15,16) Diabetes mellitus, osteoarthritis, and joint prostheses are common predisposing factors. In our case of hematogenous vertebral osteomyelitis with para-spinal abscess, culture was positive for group B streptococcus, whereas blood cultures were negative in most such cases reported in the literature. (21,26) Group B streptococcus vertebral osteo-myelitis usually has a subacute onset and is found commonly in diabetic patients. (22,25,26) In addition, contiguous infection, recent surgery, or peripheral vascular disease may predispose to group B streptococcus vertebral osteomyelitis. (26) Urinary tract infection has also been reported as the source of group B streptococcus vertebral osteomyelitis. (26,27)

Three patients had probable endocarditis but did not meet the Duke criteria for definite endocarditis. These three patients had diabetes mellitus, presented with subacute onset, and survived. We reported 7 cases of endocarditis in 1986 with high mortality rate. (28) The mortality rate in group B streptococcal endocarditis has decreased from 85% between 1938 and 1945 to 43.5% between 1962 and 1985 and to 12.9% from 1994 to 1996. (28,29)

Meningitis was found in one patient without underlying disease in this study, and she survived. Group B streptococcus meningitis can occur in both healthy and immunocompromised hosts? (3,30,31) Endogenous endophthalmitis is an uncommon clinical picture of group B streptococcal infection and was not found in either this series or the earlier study. (3,32-35) Group B streptococcal endogenous endophthalmitis is a metastatic infection, usually from endocarditis, meningitis, septic arthritis, and urinary tract infection. (32-33) In this series, there were other clinical presentations of group B streptococcal bacteremia, namely ascending cholangitis, prostatitis, mastitis, and toxic shock syndrome, that were not reported in the 1985 series. (3) Toxic shock syndrome caused by group B streptococcus is rare. Five cases (including one in this series) have been reported. (12,36-38) A pyrogenic toxin has been isolated by Schlievert et a1 (36) in a case of toxic shock syndrome associated with group B streptococcus in a y oung woman. We found all group B streptococcus strains to be susceptible to penicillin, ampicillin, cefazolin, and vancomycin. Almost all strains were resistant to tetracycline. The antibiotic susceptibility pattern in our study is similar to that reported in the literature, including strains isolated from neonates recently. (6,9,39)

CONCLUSIONS

Comparison of current cases with those reported 15 years earlier from our institution show that group B streptococcal bacteremia remains an important problem. Diabetes mellitus is still the most important underlying condition. There were fewer nosocomial cases. Pneumonia and soft tissue infections are the most common sources of bacteremia. The spectrum of infection has expanded to include ascending cholangitis, lymphadenitis, mastitis, and prostatitis. The mortality has decreased significantly during the past 15 years.

(+.) Deceased.

References

(1.) Bayer A, Chow A, Anthony B, et al: Serious infections in adults due to group B streptococci. Am J Med 1976;61:498-503

(2.) Lerner P, Gopalakrishna K, Wolinsky E, et al: Group B streptococcus (S agalactiae) bacteremia in adults: analysis of 32 cases and review of the literature. Medicine 1977; 56:457-473

(3.) Gallagher PG, Watanakunakorn C: Group B streptococcal bacteremia in a community teaching hospital. Am J Med 1985; 78:795-800

(4.) Verghese A, Mireault K, Arbeit PD: Group B streptococcal bacteremia in men. Rev Infect Dis 1986; 8:912-917

(5.) Opal SM, Cross A, Palmer M, et al: Group B streptoccal sepsis in adults and infants. Arch Intern Med 1988; 148:641-645

(6.) Colford JM Jr, Mohle-BoetaniJ, Vosti KL: Group B streptococcal bacteremia in adults, five years' experience and a review of the literature. Medicine 1995; 74:176-190

(7.) Horgan M, Edwards M, Dunagan WC: Group B streptococcal bacteremia in adults. Infect Dis Clin Pract 1997; 5:210-212

(8.) Munoz P, Llancaqueo A, Rodriguez-Creixems M, et al: Group B streptococcus bacteremia in nonpregnant adults. Arch Intern Med 1997; 157:213-216

(9.) Schugk J, Harjola V-P, Sivonen A, et al: A clinical study of beta-haemolytic groups A, B, C and G streptococcal bacteremia in adults over an 8-year period. Scand J Infect Dis 1997; 29:233-238

(10.) Cooper BW, Morganelli E: Group B streptococcal bacteremia in adults at Hartford Hospital 1991-1996. Conn Med 1998; 62:515-517

(11.) Trivalle C, Martin E, Martel P, et al: Group B streptococcal bacteremia in the elderly. J Med Microbiol 1998; 47:649-652

(12.) Cheng MM, Watanakunakorn C: Toxic shock syndrome caused by group B streptococcus. Infect Dis Clin Pract 1999; 8:46-48

(13.) Schwartz B, Schuchat A, Oxtoby MJ, et al: Invasive group B streptococcal disease in adults, a population-based study in metropolitan Atlanta. JAMA 1991; 266:1112-1114

(14.) Zangwill KM, Schuchat A, Wenger JD: Group B streptococcal disease in the United States, 1990: report from a multi-state active surveillance system. MMWR CDC Surveill Summ 1992; 41(SS-6):25-32

(15.) Farley MM, Harvey C, Stull T, et al: A population-based assessment of invasive disease due to group B streptococcus in nonpregnant adults. N Engl J Med 1993; 328:1807-1811

(16.) Jackson LA, Hilsdon P, Farley MM, et al: Risk factors for group B streptococcal disease in adults. Ann Intern Med 1995; 123:415420

(17.) Tyrrell GJ, Senzilet LD, Spika JS, et al: Invasive disease due to group B streptococcal infection in adults: results from a Canadian, population-based, active laboratory surveillance study--1996. J Infect Dis 2000; 182:168-173

(18.) The Working Group on Severe Streptococcal Infections: Defining the group A streptococcal toxic shock syndrome: rationale and consensus definition. JAMA 1993; 269:390391

(19.) Durack DT, Lukes AS, Bright DK, et al: New criteria for diagnosis of infective endocarditis: utilization of specific echocardiographic findings. Ant J Med 1994; 96:200-209

(20.) Johnson FM, Garcia A: Sepsis with group B streptococci (Streptococcus agalactiae) secondary to urinary tract infection in an adult male. J Am Geriatr Soc 1999; 47:629-630

(21.) Gordon DM, Oster CN: Hematogenous group B streptococcal osteomyelitis in an adult. South MedJ 1984; 77:643-645

(22.) McMeeking AA, Holzman R, Desiderio D, et al: Group B streptococcal osteomyelitis in an adult. NY State J Med 1987; 87:466-467

(23.) Fasano FJ Jr, Graham DR, Stauffer ES: Vertebral osteomyelitis secondary to Streptococcus agalactiae. Clin Orthop 1990; 256:101-104

(24.) Bath PMW, Pettingale KW: Group B streptococcal osteomyclitis of the spine. J R Soc Med 1990; 83:188

(25.) Elhanan G, Raz R: Group B streptococcal vertebral osteorayelitis in an adult. Infection 1993; 21:397-399

(26.) Ganapathy ME, Rissing JP: Group B streptococcal vertebral osteomyelitis with bacteremia. South Med J 1995; 88:350-351

(27.) Bauer TM, Pippert H, Zimmerli w: Vertebral osteomyelitis caused by group B streptococci (Streptococcus agalactiae) secondary to urinary tract infection. Eur J Clin Microbiol Infect Dis 1997; 16:244-246

(28.) Gallagher PG, Watanakunakorn C: Group B streptococcal endocarditis: report of seven cases and review of the literature, 1962-1985. Rev Infect Dis 1986; 8:175-188

(29.) Baddour LM and the Infectious Diseases Society of America's Emerging Infections Network: Infective endocarditis caused by beta-hemolytic streptococci. Clin Infect Dis 1998; 26:66-71

(30.) Dunne DW, Quagliarello V: Group B streptococcal meningitis in adults. Medicine 1993; 72:1-10

(31.) Barile AJ, Kallen AJ, Wallace MR: Fatal group B streptococcal meningitis in a previously healthy young adult. Clin Infect Dis 1999; 28:151

(32.) O'Brart DPS, Eykyn SJ: Septicaemic infection with group B streptococci presenting with endophthalmitis in adults. Eye 1992; 6:396-399

(33.) Nagelberg HP, Petashnick DE, To KW, et al: Group B streptococcal metastatic endophthalmitis. Am J Ophthalmol 1994; 117:498-500

(34.) Buglass TD, Romanchuk KG: Fatal case of group B streptococcal endogenous endophthalmitis. Can J Ophthalmol 1995; 30:149-150

(35.) MacGonnell TJ, Ferro A: A sore eye and meningitis. Lancet 1995; 346:1269

(36.) Schlievert PM, Gocke JE, Deringer JR: Group B streptococcal toxic shock-like syndrome: report of a case and. purification of an associated pyrogenic toxin. Clin Infect Dis 1993; 17:26-31

(37.) Holmstrom B, Grimsley EW: Necrotizing fasciitis and toxic shock-like syndrome caused by group B streptococcus. South Med J 2000; 93:1096-1098

(38.) Gardam MA, Low DE, Saginur R, et al: Group B streptococcal necrotizing fasciitis and streptococcal toxic shock-like syndrome in adults. Arch Intern Med 1998; 158:1704-1708

(39.) Lin F-YC, Azimi PH, Weisman LE, et al: Antibiotic susceptibility profiles for group B streptococci isolated from neonates, 1995-1998. Clin Infect Dis 2000; 31:76-79

TABLE 1

Nonpregnant Adult Patients With Group B Streptococcal Bacteremia

                              Present Series  Previous Series (3)
                              (1995-1999)     (1980-1984)

No. of episodes               36              28
No. of patients               35              27
Median age in years (range)   70 (26-91)      72 (31-90)
Male/female                   23/12           16/11
Diabetes mellitus             17 (48.6%)       9 (33.3%)
Malignancies                   3 (8.6%)        4 (14.8%)
Hospital-acquired bacteremia   2 (5.6%)       13 (46.4%)
Polymicrobial bacteremia       5 (13.9%)       7 (25.0%)
Overall mortality              6 (16.7%)      19 (67.9%)
TABLE 2

Sources of Group B Streptococcal Bacteremia

                                    Present Series  Previous Series (3)
Sources of Bacteremia                (1995-1999)        (1980-1984)

Pneumonia                             7 (19.4%)          5 (17.8%)
Soft tissue infections, cellulitis    7 (19.4%)          5 (17.8%)
 (including diabetic foot ulcer)
Urinary tract infection               4 (11.1%)          -
Arthritis                             3 (8.3%)           1 (3.6%)
Osteomyelitis                         3 (8.3%)           1 (3.6%)
Lymphadenitis                         2 (5.6%)           -
Meningitis                            1 (2.8%)           1 (3.6%)
Mastitis                              1 (2.8%)           -
Ascending cholangitis                 1 (2.8%)           -
Prostatitis                           1 (2.8%)           -
Intravascular device infection        -                  1 (3.6%)
Unknown                               6 (16.6%)          9 (32.1%)
TABLE 3

In Vitro Susceptibility of Group B Streptococcus

Antibiotics   No. Susceptible/No. Tested

Vancomycin           13/13 (100%)
Ampicillin           27/27 (100%)
Penicillin           27/27 (100%)
Cefazolin            27/27 (100%)
Clindamycin          23/27 (85%)
Erythromycin         17/27 (62%)
Tetracycline          2/23 (9%)
TABLE 4

Comparison of Mortality From Group B Streptococcal Bacteremia During the
Past 25 Years

                                           Period of   No. of
References           Study Sites             Study    Episodes

Gallagher and        Youngstown, Ohio      1980-1984     28
Watanakunakorn (3)
Verghese et al (4)   Boston, Mass          1978-1985     23
Opal et al (5)       Washington, DC        1975-1984     24
Colford et al (6)    San Francisco, Calif  1985-1990     29
Horgan et al (7)     St.Louis, Mo          1990-1992     58
Munoz et al (8)      Madrid, Spain         1985-1994     51
Cooper and           Farmington, Conn      1991-1996     55
Morganelli (10)
Schwartz et al (13)  Atlanta, Ga           1982-1983     56
Farley et al (15)    Atlanta, Ga           1989-1990     140
Present study        Youngstown, Ohio      1995-1999     36

                      Overall   Attributable
References           Mortality   Mortality

Gallagher and          67.9%       53.5%
Watanakunakorn (3)
Verghese et al (4)     43%         --
Opal et al (5)         41.7%       --
Colford et al (6)      37.9%       27.6%
Horgan et al (7)       19%         10.3%
Munoz et al (8)        33.3%       25.5%
Cooper and             16.4%       --
Morganelli (10)
Schwartz et al (13)    32%         --
Farley et al (15)      21%         --
Present study          16.7%       11.1%

RELATED ARTICLE: KEY POINTS

* Group B streptococcal bacteremia in nonpregnant adults is a disease of elderly patients with significant underlying diseases, particularly diabetes mellitus.

* Pneumonia, soft tissue infections, urosepsis, septic arthritis, and osteomyelitis are common presentations.

* All group B streptococcal strains are susceptible to penicillin, ampicillin, cefazolin, and vancomycin.

* The mortality has decreased significantly during the past 15 years (16.7% vs 67.9%).