Quantitative Bacterial Cultures Research Articles

Effects of Repeated Application of Emollient Cream to Premature Neonates' Skin

Emollient cream moisturizers are often used on premature newborns in neonatal intensive care units without accurate knowledge of the risks or benefits to the neonate. We prospectively compared premature neonates treated with a water-in-oil emollient cream for up to 16 days to untreated premature neonates. The study was completed in a neonatal intensive care unit on neonates admitted for respiratory distress and/or possible sepsis. Thirty-four neonates, between 29 and 36 weeks estimated gestational age, entered the study. One-half of the neonates were treated twice a day with an water-in-oil emollient cream, and the other half served as controls. The skin condition of the neonates' hands, feet, and abdomen was evaluated on entering the study and twice a week. Fungal cultures and quantitative bacterial cultures were obtained from the axilla and abdomen on entering the study and twice a week. The mean gestational age of the treated neonates was 32.3 weeks, whereas the mean gestational age of the control neonates was 32.5 weeks. The neonates treated with emollient cream demonstrated statistically less dermatitis of their hands (day 2 through day 11), their feet (day 2 through day 16), and their abdomen (day 7 through day 11). Fungal cultures and quantitative bacterial cultures of the abdomen and axilla were equivalent in both groups. These studies document that emollient cream moisturizer therapy of premature neonates decreases dermatitis without changing the microbiological flora.

Diagnostic value of bronchoalveolar lavage in patients with opportunistic and nonopportunistic bacterial pneumonia.

In 29 patients with community-acquired pneumonia, 24 patients with hospital-acquired pneumonia and 35 patients with pneumonia in the immunocompromised host the diagnostic value of bronchoalveolar lavage (BAL) with quantitative bacterial and fungal cultures was studied; 32 patients with noninfectious pulmonary diseases and 14 healthy volunteers served as controls. An infectious etiology could be established in 81% of the pneumonia patients without differences between the three groups; significant infection was associated with colony counts of > or = 10(4) cfu/ml. Prior antibiotic therapy lowered the yield of BAL culture only in community-acquired pneumonia (94% vs 55% positive cultures in untreated vs pretreated patients, p < 0.02). Furthermore the culture results were related to the radiographic extension of pulmonary infiltrates (92% positive cultures in multilobar vs 54% in lobar or segmental infiltrates, p < 0.001). Therapeutic consequences of BAL were shown by resistance of the isolated organisms to predefined empiric treatment regimens in 41% community-acquired pneumonia, 43% pneumonia in the immunocompromised host and 67% hospital-acquired pneumonia patients.

Treatment of experimental osteomyelitis with antibiotic‐impregnated bone graft substitute

The model of Norden was used to induce osteomyelitis in the left tibia of New Zealand White rabbits. Twenty-one days following inoculation, the animals had primary debridement and then were randomized into one of three treatment groups. Group I received no additional treatment; in Group II, plain hydroxyapatite beads were packed into the defect; and in Group III, gentamicin crobefat-loaded hydroxyapatite beads were packed into the defect. The animals were observed for 40 days after the primary debridement and then were killed. The intensity of infection was determined by swab cultures and quantitative bacterial cultures of the debrided material. At primary debridement, all of the animals in each group were equally infected. At the time of secondary debridement, only the animals in Group III had a statistically significant reduction in infection (p < 0.001). In this study, we demonstrated that an antibiotic-loaded osteoinductive ceramic bead can effectively eliminate bacteria from an osteomyelitic cavity.

Role of parenteral nutrition in preventing malnutrition and decreasing bacterial translocation to liver in obstructive jaundice

Surgery in patients with obstructive jaundice is associated with significant infectious complications probably due to impaired immune function and malnutrition. Total parenteral nutrition (TPN) may alleviate malnutrition but may also promote bacterial translocation (BT) from the gut. To elucidate if TPN can prevent malnutrition without promotion of BT in obstructive jaundice, 40 dogs underwent laparotomy for tissue sampling and placement of a central venous line and were allocated into one of four groups: I (PO-control) received dog chow and water ad libitum; II (PO-CBDL) underwent ligation of common bile duct (CBDL) and was fed dog chow; III (TPN-control) received TPN; and IV (TPN-CBDL) underwent CBDL and received TPN. Body weight, blood samples for liver function tests and bacterial culture, and tissues from liver and mesenteric lymph nodes (MLN) for quantitative bacterial culture and for histology were obtained prior to and 2 weeks after the experiment. The incidence of BT to MLN was 40% in the PO-CBDL and TPN-CBDL animals, which was significantly different from the other two groups (0%; p < 0.05). The incidence of BT to liver was 70% (7/10) in the PO-CBDL animals, which was significantly higher than that in groups I, III, and IV (0%, 20%, 20%, respectively) (p < 0.05). The PO-CBDL animals showed a significant decrease in body weight and prealbumin compatible with malnutrition, whereas the TPN-CBDL animals showed a significant increase in alkaline phosphatase and a consistent cholestasis on histology. The data suggest that TPN can prevent jaundice-associated malnutrition and decrease BT to liver but should be administered cautiously because it may precipitate cholestasis.

Evaluation of a one-step surgical preparation technique in dogs

Summary The efficacy of a 1-step surgical preparation technique for skin of dogs prior to elective ovariohysterectomy was evaluated. Dogs randomly assigned to group 1 (n = 30) had their skin prepared for surgery by use of a 2-step method, whereas the skin of dogs in group 2 (n = 30) was prepared for surgery by use of a commercially available product for a 1-step technique. Culture plates for quantitative bacterial counts were applied to the proposed incision site on dogs under general anesthesia after hair at the site was clipped and vacuumed but before antiseptic was applied. A second quantitative bacterial culture plate was applied to the proposed incision site after completion of the surgical preparation technique. Surgeries were routinely completed, and dogs were evaluated by physical examination the next day and at the time of suture removal (7 to 10 days after surgery) for complications. Postoperative complications were minor and consisted primarily of subcutaneous swelling, which resolved with time. All cultures obtained prior to skin preparation included bacteria or yeast. Sixteen cultures obtained after skin preparation (group 1, n = 11; group 2, n = 5) included bacteria or yeast. The total number of colonies of potential pathogens (Staphylococcus sp and Enterobacteriaceae) on the prepreparation cultures was 9,339; 4 colonies were counted on the postpreparation cultures. Potential bacterial pathogens, ie Streptococcus intermedius and gram-negative bacteria, were isolated from dogs prepared with the 2-step technique. None of the dogs that developed postoperative complications had growth on postpreparation culture plates. There was no significant difference in the percent reduction of microbial numbers after skin preparation for either group. There was a significant (P &lt; 0.05) difference between the pre- and postpreparation microbial numbers for both preparation techniques. The 1-step technique was a simple, effective, and efficient method of skin preparation in dogs undergoing elective ovariohysterectomy.

Comparative Efficacy of Bronchoalveolar Lavage and Telescoping Plugged Catheter in the Diagnosis of Pneumonia in Mechanically Ventilated Patients

The relative efficacy of telescoping plugged catheter (TPC) and bronchoalveolar lavage (BAL) in the diagnosis of pneumonia in mechanically ventilated patients has been compared in 45 subjects suspected of having pneumonia because of the presence of clinical and radiographic criteria. Diagnosis of pneumonia was strongly suggested in 25 of the 45 patients, and definitely confirmed in 10 of them. The diagnostic threshold to assess a quantitative bacterial culture as positive was a growth on BAL of > or = 10(5) cfu/ml and on TPC of > or = 10(3) cfu/ml. The BAL specimen cultures established the diagnosis in 19 cases (76 percent). In the remaining six patients, this technique did not permit the assessment of the diagnosis, which was established by other procedures (TPC, blood cultures, clinical outcome, or autopsy). False-positive results were not found. Sensitivity and specificity for BAL cultures were 76 percent and 100 percent, respectively. Telescoping plugged catheter established the presence of pneumonia in 16 patients (64 percent). Combining both techniques, the sensitivity increased up to 88 percent, maintaining specificity of 100 percent. In summary, BAL has a greater sensitivity than TPC in the diagnosis of pneumonias in mechanically ventilated patients. However, they are procedures that can complement each other.

Quantitative bacterial culture from adenoid lymphatic tissue with special reference to Haemophilus [corrected

Homogenized adenoid tissue from 55 children (28-153 months) undergoing adenoidectomy because of nasopharyngeal obstruction was investigated by means of quantitative aerobic bacterial culture. The children were divided into two groups, the hypertrophy alone group--AH (n = 29)--and the hypertrophy with longstanding secretory otitis media group--SOM (n = 26). A nasopharyngeal culture was obtained preoperatively from 38 of the cases. Non-typeable H. influenzae (NTHI) was found in twice as many cases in the AH group as in the SOM group, 21/29 (72%) compared to 11/26 (42%) (p < 0.05) and in a significantly higher mean concentrations, 5.7 x 10(5) CFU/g compared to 1.9 x 10(5) CFU/g (p = 0.02). For the other aerobic potentially pathogenic bacteria no such difference was found. The bulk of the NTHI-positive cases and the cases with the highest concentrations were found in the children below the age of 6 years. In the nasopharyngeal cultures NTHI alone or together with S. pneumoniae and/or B. catarrhalis was found in 29% of the cases in both the AH group and SOM group. NTHI was found in only 50% of the nasopharyngeal cultures corresponding to a positive quantitative culture (10/20). These findings suggest that NTHI is harboured within the adenoid and could thereby chronically stimulate the local immune defense. However, the present study indicates that there is no aerobic bacterial overload in the adenoid tissue in children with SOM compared to children without middle-ear disease.

A natural history study of experimental Staphylococcus epidermidis endophthalmitis.

The purpose of this study was to find a "threshold" quantity of organisms (i.e. inoculum) to produce clinical endophthalmitis and determine the natural course of intravitreal bacterial counts following inoculation in a rabbit model of Staphylococcus epidermidis endophthalmitis. S. epidermidis endophthalmitis was induced experimentally in 18 New Zealand white rabbits. Eyes were injected with 2.0 x 10(3) (Group I: n = 3), 2.0 x 10(4) (Group II: n = 3), 3.0 x 10(5) (Group III: n = 3), 3.0 x 10(6) (Group IV: n = 3), 3.0 x 10(7) (Group V: n = 3), or 3.0 x 10(8) (Group VI: n = 3) organisms. Serial quantitative bacterial cultures (colony counts) were performed on the vitreous every eight hours for 9 days. All eyes in Groups I and II became culture negative by 24-64 hours post-inoculation (PI). All eyes in Groups III-VI remained culture positive [approximately 600-4000 colony forming units (CFU) per cm3] at 48 to 72 hours PI and were stable for the remainder of the nine day study period. Previous work suggests that the host's inflammatory response is more important than had been recognized. Previous rabbit models of infectious endophthalmitis are known to become culture negative ("autosterilized") despite continued intraocular inflammation. This rabbit model demonstrates a "threshold" of infection where the host's immune response is overwhelmed and "autosterilization" does not occur. When inoculated with 3.0 x 10(5) or greater S. epidermidis organisms of this strain, continued active bacterial replication can now be studied in the rabbit.

The Standardization of Bronchoscopic Techniques for Ventilator-Associated Pneumonia

During the last decade, several centers have directed their research efforts at defining more efficient modalities for the accurate diagnosis ofventilatorassociated pneumonia (VAP). Accurate diagnosis is an essential prerequisite for clinical investigation. Initial studies, which correlated histologic findings and quantitative bacterial cultures of the lung with the findings of protected specimen brush cultures have stimulated clinical investigation of VAP Two diagnostic techniques, protected specimen brushing (PSB) and bronchoalveolar lavage (BAL), have been extensively investigated and have shown promising results. Advancements in the field, however, have been limited by the lack of standardization, particularly for BAL. In this communication, we attempt to standardize methodology for presently available bronchoscopic techniques and interpretation of data obtained by bronchoscopy to facilitate comparisons among investigations and to promote multicenter collaboration.

The Standardization of Bronchoscopic Techniques for Ventilator-Associated Pneumonia

During the last decade, several centers have directed their research efforts at defining more efficient modalities for the accurate diagnosis of ventilator-associated pneumonia (VAP). Accurate diagnosis is an essential prerequisite for clinical investigation. Initial studies, which correlated histologic findings and quantitative bacterial cultures of the lung with the findings of protected specimen brush cultures have stimulated clinical investigation of VAF! Two diagnostic techniques, protected specimen brushing (PSB) and bronchoalveolar lavage (BAL), have been extensively investigated and have shown promising results. Advancements in the field, however, have been limited by the lack of standardization, particularly for BAL. In this communication, we attempt to standardize methodology for presently available bronchoscopic techniques and interpretation of data obtained by bronchoscopy to facilitate comparisons among investigations and to promote multicenter collaboration.

Removal of Yersinia enterocolitica from AS-1 red cells.

The growth of Yersinia enterocolitica in AS-1 red cells was investigated so as to study the organism's proliferation kinetics and to evaluate the effect of prestorage white cell (WBC) reduction on bacterial multiplication. Twenty-four 2-unit pools of ABO-compatible whole blood were prepared and inoculated with Y. enterocolitica to final concentrations ranging from 0.3 to 132 organisms per mL. After inoculation, pools were split equally, AS-1 red cells were prepared, and 1 unit of each pair (test unit) was WBC-reduced with a WBC-reduction filter. Quantitative bacterial cultures of both WBC-reduced and control units were performed at several points throughout preparation and storage. Less than 10 percent of the inoculated organisms was recovered from blood samples taken after a 7-hour room-temperature holding period. By the end of 42 days of storage, Y. enterocolitica was recovered from unfiltered red cells in 2 of the 6 units inoculated at the lowest levels (0.3 and 0.7 organism/mL), from 8 of the 12 units inoculated at the intermediate levels (2.8, 5.2, 30.7, and 43 organisms/mL) and from 6 of the 6 units inoculated at the highest levels (98.8 and 132 organisms/mL). Positive cultures were seen as early as Day 7. In contrast, filtered units inoculated at all levels less than or equal to 98.8 organisms per mL (21/21 units) were sterile at the end of the 42-day storage period, while 2 units (2/3) inoculated at 132 organisms per mL showed growth despite filtration.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant Human DNase Inhalation in Normal Subjects and Patients With Cystic Fibrosis

To evaluate the safety of recombinant human DNase (rhDNase) in normal subjects and in patients with cystic fibrosis. Nonrandomized trial in which individuals inhaled rhDNase three times a day Monday through Friday on two consecutive weeks. The study was performed in the Clinical Research Center at the University of Washington, Seattle. Patients were recruited from the Cystic Fibrosis Center at the University of Washington. Twelve normal subjects and 14 patients with cystic fibrosis were studied (12 patients completed the protocol). The subjects and patients had to be aged 18 to 65 years and have a negative pregnancy test, if female. The normal subjects had to have a normal chest roentgenogram, be nonsmokers, and have normal pulmonary function testing. The patients with cystic fibrosis had to have a forced vital capacity greater than 40% predicted normal and have no recent exacerbation (within 2 weeks) of their lung infection or change in their medication. The study design was a repetitive dose escalation of aerosolized rhDNase. The subjects inhaled rhDNase three times a day, Monday through Friday, on 2 consecutive weeks and were rechallenged with a single dose 21 days after the last dose. Spirometry was measured before and 30 minutes after every rhDNase dose. Pulmonary function testing, serum DNase concentrations, and anti-DNase antibodies. Secondary outcome measures were dyspnea score and quantitative bacterial culture. Inhalation of rhDNase was well tolerated by all persons. There were no serious adverse reactions, and no allergic reactions were observed, even on rechallenge. No individual developed rhDNase antibodies. Improvement in both lung function and dyspnea score was observed in the adults with cystic fibrosis. Forced vital capacity was 3.2 +/- 0.3 L (mean +/- SE) on day 1 and was 3.5 +/- 0.3 L on day 12. Forced expiratory volume in 1 second was 2.1 +/- 0.2 L (mean +/- SE) on day 1 and was 2.3 +/- 0.3 L on day 12. Aerosolized rhDNase appears safe in normal subjects and in adults with cystic fibrosis and may improve lung function with short-term therapy.

The Effect of Autogenous Bone Graft Application on

A rat model was created in which contaminated wounds were closed in either the presence or absence of autogenous bone graft. The recipients of bone graft were divided into two groups--one receiving autogenous cancellous bone, the other receiving nonviable autogenous autoclaved cortical bone. Quantitative bacterial cultures were collected both at the time of wound closure and 2 weeks after closure. A significantly increased level of soft-tissue contamination was associated with wound closure in the presence of either type of bone graft, indicating an overall adverse effect on soft tissues. A critical level existed such that at initial bacterial contamination levels greater than 10(4) organisms/g tissue, final contamination levels were significantly elevated. With initial contamination levels less than 10(4) organisms/g tissue, however, final bacterial contamination levels were not significantly different. These results may help explain the different rates of infection that have been reported when delayed primary closure of open fractures is done in conjunction with autogenous bone graft.

Bronchoscopic Protected Specimen Brush and Bronchoalveolar Lavage in the Diagnosis of Bacterial Pneumonia

Despite marked improvements in antibiotic therapy, the accurate diagnosis and treatment of bacterial lower respiratory tract infection remain a challenge. The bronchoscopic protected specimen brush and bronchoscopic bronchoalveolar lavage combined with quantitative bacterial cultures can provide sensitive and relatively specific information about lower airway flora. Both of these methods require strict observance of the required protocol, careful processing of the obtained specimens, and the absence of prior antibiotic therapy to obtain best results. These procedures are also of some utility in sickle cell acute chest syndrome, bronchiectasis, and in the immunocompromised host.

Protected Bronchoalveolar Lavage: A New Bronchoscopic Technique to Retrieve Uncontaminated Distal Airway Secretions

We tested the effectiveness of protected bronchoalveolar lavage (PBAL), performed through a protected transbronchoscopic balloon-tipped (PBT) catheter, in collecting distal airway secretions with a minimal degree of contamination. The PBAL had less than or equal to 1% squamous epithelial cells in 91% of specimens and an absence of bacterial growth in 59% of patients without pneumonia. Using a threshold of 10(4) cfu/ml we had one false positive result in 33 patient without pneumonia and one false negative in 13 patients with pneumonia. Quantitative bacterial cultures of the PBAL specimens had a diagnostic sensitivity of 97% and a specificity of 92%, with a positive predictive value of 97% and a negative predictive value of 92%. The diagnostic efficiency was 96%. The presence of intracellular organisms in much greater than or equal to 2% of the recovered alveolar cells (Giemsa stain) was seen in all but two patients with pneumonia (on corticosteroids) and in none of the patients without pneumonia. Gram stains of the PBAL specimens were positive in all but one patient with pneumonia and negative in all but one patient without infection (patient with endobronchial narrowing secondary to neoplasm with false positive cultures). Either the Giemsa or the Gram stain was positive in all patients with pneumonia, allowing early and accurate diagnosis of lower respiratory tract infection before the results of cultures were available. The time off antibiotic therapy before bronchoscopy did not affect the result of PBAL cultures, contrary to what we observed for the protected brush specimen.

Suppression of the human mucosal‐related colonic microflora with prophylactic parenteral and/or oral antibiotics

The purpose of this investigation was to assess the effects of preoperative administration of parenteral antibiotics with or without concomitant preoperative administration of oral antibiotics on the colonic mucosal-related microflora. Thirty-one patients were studied in a prospective fashion. Group A patients (n = 8) had colonoscopic mucosal biopsies performed after mechanical bowel preparation. Group B patients (n = 5) received neomycin and erythromycin (NE), 1 g each following mechanical bowel preparation, at 1, 2, and 11 p.m. the evening prior to either elective colon resection (n = 2) or prior to colonoscopic biopsy (n = 3). Emergent trauma patients who had left colon or sigmoid perforations due to gunshot wounds requiring segmental resection comprised group C (n = 7). These patients received cefoxitin or cefotetan 2 g intravenously preoperatively. Individuals in group D (n = 11) all had elective left hemicolectomies or sigmoid resections due to nonobstructing malignancies. These patients underwent the same regimen as group B patients in addition to receiving intravenous cefoxitin perioperatively. Quantitative and qualitative bacterial cultures as well as scanning electron microscopy (SEM) were used to study the mucosa-associated flora. Tissue for culture and SEM were obtained from the pathologic specimen immediately after removal. The interval between the dosage of parenteral antibiotics to tissue removal was 3 hours in both groups. Anaerobic and aerobic counts were suppressed the greatest in patients receiving both oral and parenteral antibiotics (p = 0.0001). Mean anaerobic counts decreased from 3.4 X 10(7) in group A to 1.8 X 10(2) (mean cfu/g) in group D patients. Mean aerobic counts in group A decreased from 3.7 X 10(6) to 64 (mean cfu/g) in group D.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of commonly used bowel preparations on the large bowel mucosal-associated and luminal microflora in the rat model

Studies of colonic microflora have indicated there are two distinct populations, one intraluminal and one mucosal surface-associated. This investigation further characterizes the mucosal surface microflora and assesses the effects of common preoperative bowel preparations on both microflora. Quantitative and qualitative bacterial cultures and scanning electron microscopy were used to study the microflora in five groups of seven rats each: control; intraoperative colonic instillation of ten percent povidone-iodine for 20 minutes; mechanical preparation with magnesium citrate; mechanical preparation followed by intramuscular cefoxitin (30 milligrams per kilogram) one hour preoperatively; and mechanical preparation followed by oral neomycin sulfate and erythromycin base (15 milligrams/kilogram each) given by gavage tube 18, 14, and 4 hours preoperatively. Microflora on the mucosal surface was visualized by scanning electron microscopy in all groups except the neomycin/erythromycin group. Results showed fewer bacterial isolates recovered from the mucosal surface compared with the lumen, as well as several log10 units lower for each bacterial classification. The greatest suppression of both microflora was seen in the neomycin/erythromycin group. Total aerobic and anaerobic luminal counts decreased by 3.7 (P less than 0.009) and 6.3 (P less than 0.009) log10 units, while total aerobic and anaerobic wall counts decreased by 2.3 (P less than 0.009) and 2.8 (not significantly) log10 units, respectively. Lesser reductions were noted in the povidone-iodine group (P less than 0.009, P less than 0.009, P less than 0.009, and P less than 0.048, respectively). There were no statistically significant reductions in either total aerobic or anaerobic counts in the mechanical preparation or cefoxitin groups. These results indicate that neomycin/erythromycin is the most effective regimen in reducing both microflora.

Enteric Function in Cats after Subtotal Colectomy for Treatment of Megacolon

The enteric function of four cats that had undergone subtotal colectomy for megacolon was compared with that of four normal cats. All cats were fed the same diet before and during the study. History, physical condition, body weight, blood chemistry panel, fasting and postprandial serum bile acids, serum cobalamin concentration, serum folate concentration, fecal weight, fecal water content, fecal fat content, fecal osmolality and electrolyte concentration, quantitative anaerobic fecal bacterial culture, partial thromboplastin time, prothrombin time, breath hydrogen concentration, urinary calcium, phosphorus and electrolyte concentrations, and abdominal radiographic examination with air contrast studies (pneumocolon) were examined. The four cats treated surgically were healthy and thriving and, in general, enteric function was similar to the controls. Bowel movements occurred only slightly more frequently with no significant differences in fecal volume or water content. Serum cobalamin concentrations were significantly higher in cats treated surgically. Fecal sodium concentrations were high and fecal potassium concentrations were low. Results of this study did not show any significant subclinical evidence of abnormal bowel function in cats after subtotal colectomy.

Oxygen as an Antibiotic

Previous experimentation with the guinea pig skin injection model showed that altering the fraction of inspired oxygen had a significant effect on infectious necrosis. Using the same model, we performed quantitative bacterial cultures to determine the number of viable injected bacteria 24 and 48 hours after injection. Animals were randomized to receive 12%, 21%, and 45% inspired oxygen. A significant decrease in bacterial number was seen at 45% inspired oxygen between 24 and 48 hours, and a significant decrease occurred at 48 hours between 12% and 45% inspired oxygen. These results demonstrated a prominent role for oxygen in bacterial clearance and host defense.

Comparative Evaluation of Cefuroxime Axetil and Cefaclor for Treatment of Acute Bacterial Maxillary Sinusitis

Cefuroxime axetil, a new beta-lactamase-stable cephalosporin, was compared with cefaclor for the treatment of acute bacterial maxillary sinusitis in 106 adult patients. Direct sinus aspirations for quantitative bacterial culture were done for all patients before treatment; aspiration was repeated for most patients after treatment. Pretreatment sinus aspirates were positive for 63 of 134 sampled sinuses. Of specimens yielding at least 10(4) CFU/mL, Haemophilus influenzae (38%) and Streptococcus pneumoniae (37%) were the most common pathogens. Ten (42%) of 24 strains of H influenzae, 2 (40%) of 5 Haemophilus parainfluenzae, and all 3 isolates (60%) of Branhamella catarrhalis produced beta-lactamase. Cefuroxime axetil, 250 mg twice a day, was compared with cefaclor, 500 mg three times a day. Among culture-positive sinuses, bacteriologic cure was achieved in 36 (95%) of 38 sinuses and 15 (71%) of 21 sinuses treated with cefuroxime axetil and cefaclor, respectively. The overall frequencies of adverse events were similar between drugs, although cefuroxime axetil was associated with more frequent diarrhea. Cefuroxime axetil was an effective therapy for the treatment of acute bacterial maxillary sinusitis in adults.