TABLE 1. Number and type of microorganisms recovered only from the anaerobic (lytic) blood culture bottle: Mid-February 1990 to September 1990

Facultative organisms Anaerobes

Hospital A (total number of blood

cultures submitted--3876)

Hospital B (total number of blood

cultures submitted--3188)

Staphylococcus aureus 2 Bacteroides fragilis 4 Coagulase negative staphylococci 15 B. oralis gp. 2 Viridans group streptococci 10 B. uniformis 2 Streptococcus pneumoniae 2 B. thetaiotaomicron 3 Group B streptococcus 1 B. caccae 1 Enterococcus sp. 7 Clostridium perfringens 3 Escherichia coli 14 P eptostreptococcus i Klebsiella pneumoniae 2 Peptococcus 1 Enterobacter cloacae 4 Propionibacterium acnes 2 Proteus mirabilis 1 Diphtheroids 3 Totals 58 22 Percentage 1.5% 0.57%

S. aureus 2 B. fragilis 3 Coagulase negative staphylococci 18 B. oralis 1 Viridans group streptococci 4 B. buccae 2 Enterococcus spp. 2 B. eggerthii 1 Lactobacillus spp. 1 B. loescheii 1 E. coli 5 C. perfringens 2 K. pneumoniae 1 Peptostreptococcus spp. 2

Lactobacillus spp. 3 Totals 33 14 Percentage 1.04% 0.44%

just anaerobes. Our two-bottle system was selected primarily for its ability to detect as many different kinds of or- ganisms as possible. At least for now I believe we are on the right course.

References 1. Sharp, S. E. 1991. Routine anaerobic

blood cultures: still appropriate today?

Clin. Microbiol. Newslett. 13:179- 181.

2. Murray, P. P. 1985. Determination of the optimum incubation period of blood culture broths for the detection of clinically significant septicemia. J. Clin. Microbiol. 2:481-485.

3. Courcol, R. J., A. V. Durocher, M. Roussel-Delvallez, A. Fruchart and G. R. Martin. 1988. Routine evalua- tion of Bactec NR-16A and NR-17A

media. J. Clin. Microbiol. 23:262- 266.

4. Levi, M. H., et al. 1988. Rapid detec- tion of positive blood cultures with the Bactec NR-660 does not require first- day subculturing. J. Clin. Microbiol. 26:2262-2265.

5. Martin, W. J., P. A. Wilhelm, and D. Bruckner. 1984. Recovery of anaero- bic bacteria from vented blood-culture bottles. Rev. Infect. Dis. 6:559-561.

Case Report

Simultaneous ShigeUa and Salmonella Septicemia in an AIDS Patient

Caries Alonso, Ph.D. Ferran Sanchez, Ph.D. Beatriz Mirelis, M.D. Servei de Microbiologia

Josep Cadafalch, M.D. Servei de Medicina lnterna Hospital Universitari de la Santa Creu i

St. Pau Barcelona, Spain

A 36-yr-old homosexual male was admitted to the hospital after a 3-d history of severe diarrhea, colic ab- dominal pain and fever. Physical ex- amination revealed an axillary temperature of 38.9°C, a pulse rate of 120 beats per minute, and blood pres- sure of 110/80 mmHg. Initial analyti- cal blood data included 3,500 white blood cells/ram 3 (45% polymorphonu- clear leukocytes, 26% band cells, 14% lymphocytes, 14% monocytes, 1% eosinophils, and 0% basophils), hemo- globin 12.5 g/dl, and MCV 83.7 fl.

Three blood cultures were obtained and three fecal samples were submitted to the Microbiology Laboratory for bacterial, parasitic, and virologic eval- uation. HIV serology was also per- formed.

Over the next 5 d no improvement was observed and he had lost 9 kg since the onset of symptomatology. Ampicillin therapy (1 g/qid i.v.) was administered empirically but the pa- tient's general status and diarrhea did not improve. Two days later Salmo-

nella typhimurium and Shigella flex-

134 0196o4399/92/$0.00 + 03.00 © 1992 Elsevier Science Publishing Co., Inc. Clinical Microbiology Newsletter 14:17,1992

neri serovar 3 were isolated from one blood culture, and both microorgan- isms were also recovered from the three fecal samples. No other enteric pathogens were detected. The Salmo- nella isolate was susceptible to ampi- cillin, chloramphenicol, cefotaxime, trimethoprim/sulfamethoxazole (TMP/ SMX), norfloxacin, and ciprofloxacin; the Shigella isolate was resistant to ampicillin, chloramphenicol, and TMP/SMX and susceptible to cefotax- ime, norfloxacin, and ciprofioxacin. Antimicrobial treatment was changed to norfloxacin (400 mg/bid p.o.) and the patient's fever and diarrhea disap- peared 1 d later; the patient was dis- charged 13 d after admission. Two stool specimens taken within 2 wk were negative for enteric pathogens. No other blood cultures were per- formed. The patient was found to be positive for HIV antibodies by EIA and Western-blot techniques and to have OKT4 and OKT8 blood values of 13 l/ram 3 and 290/mm 3, respectively. In 2 mo normal weight was regained. Presently, he is receiving AZT and TMP/SMX treatment and his progress is satisfactory. Since discharge he has suffered from two episodes of gastro- enteritis (caused by Giardia lamblia and adenovirus, respectively); stool cultures did not yield either Salmonella or Shigella.

In summary, the patient is a homo- sexual with HIV infection presenting with an episode of enteritis and poly- microbic septicemia caused by Salmo- nella typhimurium and Shigella flexneri as his first manifestation of AIDS.

Discussion Enteritis by Salmonella is well doc-

umented in AIDS and there seems to be a higher incidence of this infection in such patients (1). It is also known that the incidence of septicemia caused by this microorganism in AIDS pa- tients with Salmonella gastroenteritis is very high--80% in AIDS patients ver- sus 5% in the general population ( l ) - - and that infection is frequently recurrent and severe. Long-term treat- ment is required as with other infec- tions in HIV patients. Several reasons have been suggested to explain these phenomena, including impaired cell- mediated immunity, the use of agents that decrease gastric acidity, and im- paired reticuloendothelial cell function (as in hemolysis state).

Shigella septicemia is generally con- sidered a rare event and has been de- scribed mainly in children suffering malnutrition but also in children with neoplasia or under immunosuppressive therapy. The species most frequently implicated in septicemia are S. dysen- teriae and S. flexneri. Septic6mia in adults has also been reported in serious systemic illnesses such as diabetes, liver diseases, renal transplantation, and hemolytic states (2). A review of seven cases of Shigella septicemia in AIDS patients was recently published (3). Infection in this situation may be recurrent and even fatal. Although the species most frequently isolated in de- veloped countries is S. sonnei, most cases of septicemia in AIDS patients have been related to S. felxneri.

Finally, it should be noted that the

patient did not improve until norfloxa- cin, an antimicrobial agent to which both strains were susceptible (S. typhi- mium, MIC: 0.12 ~g/ml; S. flexneri MIC: 0.06 p,g/ml) but not indicated for use in generalized infections, was administered. Treatment with ampicil- lin was not successful: the Salmonella isolate was susceptible (MIC: 1 i~g/ml) but the Shigella isolate was resistant (MIC: 128 Ixg/ml). This case supports the opinion that Shigella septicemia is not self-limiting in adults suffering from AIDS. The effectiveness of nor- floxacin could have been related to its action on focal infection (enteritis) and perhaps also to the concentrations reached in serum. When norfloxacin is orally administered serum levels are reported to reach a peak of 1.5 ~g/ml (tt/2:3.3 h), which was >10× the MIC of these microorganisms (4).

References 1. Sperber, S. J. and C. J. Schleupner.

1987. Salmonellosis during infection with human immunodeficiency virus. Rev. Inf. Dis. 9:925-934.

2. Morduchowicz G. et. al. 1987. Shi- gella bacteremia in adults (a report of five cases and a review of the litera- ture). Arch. Int. Med. 147:2034--2037.

3. Baskin D. H., J. D. Lax, and D. Barenberg. 1987. Shigella bacteremia in patients with the acquired immuno- deficiency syndrome. Am. J. Gastr. 82:338-341.

4. Wolfson J. S., and D. C. Hooper. 1989. Fluoroquinolones antimicrobial agents. Clin. Microbiol. Rev. 2:378- 424.

National AIDS Forum

Atlanta, Georgia, was the site of the Fifth National Forum on AIDS, Hepa- titis, and Other Blood-Borne Diseases, held March 29 through April 1, 1992. Some interesting statistics and conclu- sions were reported from that confer- ence: (i) Fifty percent of the needle- sticks in hospitals are caused by nee- dles used to access intravenous ports and inspection sites and not by needles

used to pierce the skin. (ii) Sixty-four percent of sharps injuries occur in nursing personnel, 3% in laboratory personnel. Twenty-eight percent were associated with i.v. lines, 18% with phlebotomy, and <4% with finger or heelstick procedures. (iii) Despite the introduction of universal precautions in 1987, needlestick and sharps injuries in healthcare workers have not been reduced significantly. Recapping pro- cedures still appear to be a major fac- tor in needlestick injuries. The use of

in-room needleboxes has not signifi- cantly affected these rates, but educa- tional programs have. (iv) Healthcare workers have an inadequate under- standing of the epidemiology, patho- genesis, risks in transmission of, and universal precautions against blood- borne infections. (v) Healthcare work- ers in low-prevalence areas are less likely to follow universal precautions and are selectively motivated to be more careful when caring for known HIV-positive patients. Adherence to

Clinical Microbiology Newsletter 14:17,1992 © 1992 Elsevier Science Publishing Co., Inc. 0196-4399/92/$0.00 + 03.00 135