[Clinical and molecular study in a family with multiple osteochondromatosis]

We present two cases of a family with the diagnosis of multiple osteochondromatosis, which was confirmed by molecular study with nonsense in heterozygosis mutation c.1219CT, (p.Gln407Stop) in the EXT1 gene. In these cases, the Madelung deformity was presented in one patient as an uncommon finding and chondrosarcoma as a feared complication in the other case, highlighting intrafamilial variation, which is why individual and interdisciplinary evaluation is recommended. In addition, before a genetic entity should provide adequate and timely family genetic counseling to all its members.

Persistence of Pseudomonas aeruginosa in a pulmonary nodule with late relapse

Lung nodules are common diagnostic challenges in hematopoietic stem cell transplantation and solid organ transplantation. Pseudomonas aeruginosa is a known cause of lung abscess in these patients, but its ability to persist for months in a quiescent lung nodule and later cause recurrent infection is not well known or documented. A patient with a history of acute pre-B-cell lymphoblastic leukemia had enlargement and cavitation of a small right upper lobe pulmonary nodule 10 months after allogeneic hematopoietic stem cell transplantation. The nodule was the remnant of a presumed P. aeruginosa septic embolus that occurred 2.5 months after transplantation. With antibiotic treatment, the nodule had shrunk in size to <1 cm and remained stable. Transthoracic needle aspiration grew P. aeruginosa indistinguishable by molecular typing from isolates obtained 7.5 months earlier from blood and bronchoalveolar lavage fluid. Sub-centimeter pulmonary nodules attributable to previously treated P. aeruginosa may harbor viable organisms and lead to recrudescent infection.

Doppler-Ultrasound measurements in renal allografts depend on the patient’s body position

Background: Due to anatomical reasons a position-dependent renal allograft artery stenosis is being discussed (e.g. only in patient’s upright position). The tortuous course of the allograft artery complicates the direct, angle-dependent measurement of maximum systolic flow velocities (vmax). So indirect signs such as intraparenchymal vmax and resistance index might be helpful, but it is unknown how these values change physiologically when patient’s body position changes. Patients and methods: We examined renal allografts of 60 patients (38 male, 22 female) with stable graft function using B-Mode-, colour-coded duplex-sonography and pulsed-wave-Doppler. We measured vmax and RI-values of three interlobar arteries in the cortex and allograft artery in the hilus in patients standing upright and in horizontal position. Corresponding values were analyzed for significant differences. Results: Intraparenchymal RI-values and vmax were significantly reduced in patients upright compared to the horizontal position (16 %, MW=0.59 vs. MW=0.70, p < 0.001 resp. 6 %, MW=30.18 cm/s vs. MW=32.17 cm/s, p = 0.045). Similar results could be detected in the renal hilus. Conclusions: Patients with stable graft-function show significant, position-dependent differences of the intraparenchymal and hilar RI-values and maximal systolic flow velocities. These changes of Doppler parameters has to be kept in mind for the correct diagnosis of a position dependent allograft artery stenosis.

Genetic stability in the Icelandic horse breed

Despite the Icelandic horse enjoying great popularity worldwide, the breed's gene pool is small. This is because of a millennium of isolation on Iceland, population crashes caused by natural disasters and selective breeding. Populations with small effective population sizes are considered to be more at risk of selection pressures such as disease and environmental change. By analysing historic and modern mitochondrial DNA sequences and nuclear coat colour genes, we examined real-time population dynamics in the Icelandic horse over the last 150 years. Despite the small gene pool of this breed, we found that the effective population size and genetic profile of the Icelandic horse have remained stable over the studied time period.

Cytochrome b sequences of ancient cattle and wild ox support phylogenetic complexity in the ancient and modern bovine populations

Mitochondrial DNA has been the traditional marker for the study of animal domestication, as its high mutation rate allows for the accumulation of molecular diversity within the time frame of domestic history. Additionally, it is exclusively maternally inherited and haplotypes become part of the domestic gene pool via actual capture of a female animal rather than by interbreeding with wild populations. Initial studies of British aurochs identified a haplogroup, designated P, which was found to be highly divergent from all known domestic haplotypes over the most variable portion of the D-loop. Additional analysis of a large and geographically representative sample of aurochs from northern and central Europe found an additional, separate aurochs haplotype, E. Until recently, the European aurochs appeared to have no matrilinear descendants among the publicly available modern cattle control regions sequenced; if aurochs mtDNA was incorporated into the domestic population, aurochs either formed a very small proportion of modern diversity or had been subsequently lost. However, a haplogroup P sequence has recently been found in a modern sample, along with a new divergent haplogroup called Q. Here we confirm the outlying status of the novel Q and E haplogroups and the modern P haplogroup sequence as a descendent of European aurochs, by retrieval and analysis of cytochrome b sequence data from twenty ancient wild and domesticated cattle archaeological samples.

Genotypic analysis of invasive Streptococcus pneumoniae from Mali, Africa, by semiautomated repetitive-element PCR and pulsed-field gel electrophoresis

As part of a large, ongoing study of invasive infections in pediatric patients in Bamako, Mali, 106 cases of invasive pneumococcal disease were identified from June 2002 to July 2003 (J. D. Campbell et al., Pediatr. Infect. Dis. J. 23:642-649, 2004). Of the 12 serotypes present, the majority of isolates were not contained in PCV7 (the 7-valent pneumococcal conjugate vaccine), including 1 isolate that was serotype 1, 12 isolates that were serotype 2, 58 isolates that were serotype 5, 7 isolates that were serotype 7F, and 1 isolate that was serotype 12F. To determine whether clonal dissemination of the predominant serotypes had taken place, genotyping was performed on 100 S. pneumoniae isolates by using two methods: pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA, and the Bacterial Barcodes repetitive-element PCR (rep-PCR) method. Criteria for delineating rep-PCR genotypes were established such that isolates of different serotypes were generally not grouped together. The two methods were equally discriminatory within a given pneumococcal serotype. PFGE separated the isolates into 15 genotypes and 7 subtypes; rep-PCR separated isolates into 15 genotypes and 6 subtypes. Using either method, isolates within serotypes 2, 5, and 7 formed three large, separate clusters containing 1 genotype each. Both methods further distinguished related subtypes within serotypes 2 and 5. Interestingly, one of the PFGE subtypes of serotype 5 is indistinguishable from the Columbia(5)-19 clone circulating in Latin America since 1994. The data support that serotypes 2 and 5 were likely to be the result of dissemination of particular clones, some of which are responsible for invasive disease over a broad population range.

Biological effects of imidazolium ionic liquids with varying chain lengths in acute Vibrio fischeri and WST-1 cell viability assays

Detailed biological studies of methyl- and some ethylimidazolium ionic liquids in luminescent bacteria as well as in the IPC-81 (leukemia cells) and C6 (glioma cells) rat cell lines are presented. Effective concentrations in these test systems are generally some orders of magnitude lower than effective concentrations [corrected] of the conventional solvents acetone, acetonitrile, methanol, and methyl t-butyl ether. No general influence of the anionic compound in the ionic liquids on toxicity could be found, although they seem to modulate toxicity in some cases. The clear influence of the alkyl chain length on toxicity was quantified by linear regression analysis. Alkyl chain length of the longer alkyl chain was varied from 3 to 10 carbon atoms. Consequences for a design of sustainable alternative solvents are briefly sketched.

Comparison of automated culture systems with a CFR/USP-compliant method for sterility testing of cell-therapy products

BACKGROUND

Although widely used, commercially available automated culture methods are not US Food and Drug Administration-approved for sterility testing of cell-therapy products. For cell-therapy products regulated under Section 351 of the Public Health Service Act, sterility testing must be performed by the methods described in 21 CFR 610.12 and USP <71> (CFR/USP method), or by methods demonstrated to be equivalent.

METHODS

Two automated methods, BacT/Alert (BTA; bioMerieux) and Bactec (Becton Dickinson), were compared with the CFR/USP method. Representative mononuclear cell (MNC) products were formulated using six different product media. MNC product aliquots containing 10-50 x 10(6) cells in a 0.5 mL volume were seeded with organisms, and cultured for 14 days in aerobic and anaerobic bottles of each system. Ten different organisms at target concentrations of 10 and 50 colony-forming units (CFU) per bottle were tested.

RESULTS

Positives were detected in a mean (range) of 72% (7-100%) of cultures for CFR/USP, 82% (0-100%) for BTA, and 93% (57-100%) for Bactec. For nine of the 10 organisms tested, overall detection rates for BTA and Bactec were equivalent to or higher than CFR/USP. Of the six product media tested, detection of organisms was impaired only by the medium containing multiple antibiotics: this occurred in all three systems. Both BTA and Bactec had shorter times to detection than the CFR/USP method, with overall means (ranges) of 87 (24-264) h for CFR/USP, 24 (12-54) h for BTA, and 33 (12-80) h for Bactec. Detection occurred consistently within 7 days for both BTA and Bactec, but not for CFR/USP.

DISCUSSION

Both BTA and Bactec are superior to the CFR/USP method for overall detection and time to detection of organisms in MNC products suspended in commonly used media. These data support general use of either BTA or Bactec for sterility testing of a variety of cell-therapy products, and suggest that a 7-day culture period is sufficient to detect clinically relevant organisms. These results confirm the need for bacteriostasis and fungistasis testing of antibiotic-containing products, even when antibiotic-binding substances are used.

Mandibular ramus flexure and gonial eversion as morphologic indicators of sex

Recently, two mandibular traits--ramus flexure and gonial eversion--have come under close scrutiny (Loth & Henneberg 1996, 2000). The present study investigates the reliability of these two traits when each is applied as a single and independent indicator of sex, including the question of repeatability. The investigation was designed to give insights into possible confounding factors such as age and remodeling after tooth loss. Two samples, one of forensic (N = 153) and one of archaeological provenance (N = 80), were examined. The forensic sample was evaluated by a single observer while the archaeological sample was independently scored by three different observers. The results document that age and localized tooth loss seriously reduce the accuracy of these traits. For ramus flexure, male accuracy was only 66%, while female accuracy was even lower (32%). Overall accuracy was 59%. It is believed that the original scoring system devised by Loth and Henneberg (1996) creates an inherent bias in favor of males. For gonial eversion, a similar picture emerged (75.4% for males, 45.2% for females and 69.3% overall accuracy). Furthermore, both indicators are prone to intra- as well as inter-observer bias. While both possess some merit as sex indicators, they show marked functional and adaptive responses and may not be suitable for all samples.

Multidrug-resistant Corynebacterium striatum pneumonia in a heart transplant recipient

Corynebacterium striatum is a rare, but likely underreported, cause of serious infections in immunocompromised hosts and generally is susceptible to multiple classes of antimicrobial agents. Here we report the first case of C. striatum infection in a solid organ transplant recipient. Three years after heart transplantation, a 58-year-old man developed bilateral pneumonia and pulmonary embolism. He did not improve with levofloxacin, piperacillin/tazobactam, and heparin treatment. A homogeneous population of abundant gram-positive rods was repeatedly demonstrated in sputum and bronchoalveolar lavage fluid, and C. striatum was grown in pure culture. The isolate was unusual for its multidrug-resistant (MDR) antimicrobial susceptibility pattern. The pneumonia resolved with 4 weeks of vancomycin therapy, in combination with rifampin given only during the first 2 weeks of treatment. The isolation of coryneforms ("diphtheroids") is often attributed to contamination. Their abundant presence on direct examination of specimens and/or their growth in pure culture suggest a pathogenic role, however, and indicate the need for accurate microbiological identification, particularly in immunocompromised hosts who have been hospitalized and previously treated with antibiotics. Combination therapy that includes vancomycin may be the most prudent treatment for MDR C. striatum infections.

The use of oral washes to diagnose Pneumocystis carinii pneumonia: a blinded prospective study using a polymerase chain reaction-based detection system

Pneumocystis carinii pneumonia (PCP) can be diagnosed by direct microscopic examination of induced sputum or by bronchoalveolar lavage (BAL). However, many institutions have little diagnostic success with induced sputum, and BAL is invasive and expensive. This prospective, blinded study assessed oral washes as a more convenient specimen than either sputum or BAL fluid and used a dissociation-enhanced lanthanide fluoroimmunoassay time-resolved fluorescent hybridization polymerase chain reaction (PCR) detection system that is feasible for clinical laboratories. The study assessed 175 oral washes, each paired with either an induced sputum that was positive for Pneumocystis or a BAL sample. The PCR test based on the Pneumocystis major surface glycoprotein primers had a sensitivity of 91% and a specificity of 94%, compared with a test based on mitochondrial large subunit rRNA primers, which had a sensitivity of 75% and a specificity of 96%. These results suggest that oral washes can provide a useful sample for diagnosis of PCP when a sensitive PCR detection system is used.

[The mad man and his doctor]

There weren't specialist physicians for mental diseases in Antiquity, but mad men were usually attended to by doctors from the time of Hippocrates to Late Antiquity. The therapies were generally physical (pharmaceutical and dietetic), but some schools of medicine (Asclepiades, Celsus, Caelius Aurelianus) took into consideration the psychological behaviour and experimented with a sort of relational therapy of madness.

Resistance to multiple fluoroquinolones in a clinical isolate of Streptococcus pyogenes: identification of gyrA and parC and specification of point mutations associated with resistance

A strain of Streptococcus pyogenes resistant to multiple fluoroquinolones was isolated from the blood of an immunocompromised patient. Resistance to fluoroquinolones in S. pyogenes has not been previously studied. Compared to 10 sensitive strains of S. pyogenes, the fluoroquinolone-resistant clinical isolate of S. pyogenes presented point mutations in gyrA, predicting that serine-81 was changed to phenylalanine and that methionine-99 was changed to leucine, and in parC, predicting that serine-79 was changed to tyrosine. The mechanism of fluoroquinolone resistance in this isolate of S. pyogenes appears to be analogous to previously reported mechanisms for Streptococcus pneumoniae.

Evaluation of a new culture medium for Borrelia burgdorferi

We evaluated the new MPM medium for the growth of Borrelia burgdorferi. All 18 blood samples from 17 patients with Lyme disease were negative. Growth studies showed that by day 4, most organisms in MPM were not viable. Our results reinforce the use of BSK medium as the primary choice for growing B. burgdorferi.

Detection of Legionella by PCR in respiratory specimens using a commercially available kit

Using polymerase chain reaction (PCR) for the detection of pathogens that are difficult to grow, such as Legionella species, may reduce difficulties encountered with culture and immunofluorescent staining. We evaluated a commercial PCR and hybridization kit, designed for environmental samples, for the detection of Legionella in respiratory specimens. Sixteen Legionella species cultures tested positive with the Perkin Elmer Legionella EnviroAmp Amplification and Detection kits (Perkin Elmer, Foster City, Calif). The assay detected as few as 100 colony-forming units per milliliter of spiked bronchoalveolar lavage (BAL) fluid, and no false-negative results were obtained. PCR inhibition by blood in the specimens was removed by washing pelleted specimens in sterile distilled water. Of 126 specimens screened with the kit, 1 induced sputum and 3 BAL specimens were positive by PCR. All 4 were validated as true-positive results by culture or serologic testing. The entire PCR and hybridization assay can be completed in less than 6 hours, whereas isolation and identification by culture requires up to 12 days, and serologic conversion may not be demonstrated for weeks. Molecular techniques based on direct extraction and amplification of DNA from respiratory specimens nay be useful for the timely diagnosis of legionellosis.

Infections with Roseomonas gilardii and review of characteristics used for biochemical identification and molecular typing

Roseomonas is a recently described genus of gram-negative coccobacilli formerly designated as "pink-coccoid" groups I through IV by the Centers for Disease Control and Prevention (Atlanta, Ga) because of the organism's characteristic pink colonies. Since 1991 we have isolated Roseomonas from eight patients; in seven from blood cultures and in one from a skin lesion. The seven blood isolates were from patients with clinically significant underlying diseases who had central venous catheters in place; the majority were associated with polymicrobial catheter infections. Additional characteristics of their infections are described. The eight isolates had originally been identified by us as Centers for Disease Control (CDC) pink-coccoid group III. These organisms were re-identified using the criteria of Rihs et al, and all isolates fit most closely with Roseomonas gilardii. Antibiotic profiles were fairly homogeneous showing susceptibility to many antibiotics, but uniform resistance to cefoxitin, ceftazidime, and piperacillin. Attempts to determine whether the isolates were the same strain by pulsed-field gel electrophoresis suggested that 3 of the isolates were similar. Random amplified polymorphic DNA analysis, however, demonstrated that each of the eight isolates was a unique strain.

Lack of clinical utility of bronchoalveolar lavage cultures for cytomegalovirus in HIV infection

This study assessed the presence of cytomegalovirus (CMV) in bronchoalveolar lavage (BAL) in three subpopulations of HIV-infected patients and correlated its presence with clinical status during 3 mo of follow-up. Nineteen asymptomatic volunteers, six patients with CMV retinitis, and 46 patients with acute pulmonary symptoms underwent BAL and were assessed for CMV by cytopathology, conventional shell vial cultures, and antigen detection. Transbronchial biopsies were also obtained when possible and evaluated for histopathologic changes of CMV. All patients were followed for approximately 3 mo. Cytomegalovirus was detected in BAL in nine of 19 (47%) asymptomatic volunteers, in all six patients with CMV retinitis, and in 33 of 46 (72%) patients with pulmonary symptoms. Only one symptomatic patient with a positive CMV BAL culture developed clinically significant CMV pulmonary disease; this patient developed disseminated CMV and died. The only other death occurred in a patient with CMV retinitis who developed staphylococcal bacteremia. None of the asymptomatic volunteers or patients with CMV retinitis developed evidence of CMV pneumonia or any other organ disease with CMV. Cytomegalovirus is frequently detected in BAL from HIV-infected patients regardless of their pulmonary symptoms and its presence does not clinically predict significant pulmonary morbidity or mortality in 3 mo of follow-up.

Comparison of PCR-based approaches to molecular epidemiologic analysis of Clostridium difficile

Representative isolates of the 10 serogroups of Clostridium difficile and 39 clinical isolates (30 toxigenic and 9 nontoxigenic), including 5 isolates from a confirmed nosocomial outbreak, were analyzed by using two previously described arbitrary-primer PCR (AP-PCR) molecular typing methodologies (AP-PG05 and AP-ARB11) and PCR ribotyping. The two AP-PCR methods investigated gave comparable results; AP-PG05 and AP-ARB11 identified 8 and 7 groups among the serogroup isolates and classified the clinical isolates into 21 and 20 distinct groups, respectively. PCR ribotyping also identified 8 unique groups among the serogroup isolates but classified the clinical isolates into 23 groups. In addition, when results obtained by the PCR methods were compared with typing data generated by pulsed-field gel electrophoresis (PFGE), PCR ribotyping and PFGE were found to be in agreement for 83% (29 of 35) of isolates typeable by both techniques while AP-PG05 was in agreement with PFGE for 60% (20 of 33) and AP-ARB11 was in agreement with PFGE for only 44% (17 of 36). These results indicate that PCR ribotyping is a more discriminatory approach than AP-PCR for typing C. difficile and, furthermore, that this technique generates results that are in higher concordance with those obtained by using an established method for differentiating isolates of this organism on a molecular level than are results generated by using AP-PCR.

Comparison of pigment production and motility tests with PCR for reliable identification of intrinsically vancomycin-resistant enterococci

Forty-eight clinical isolates identified as either Enterococcus faecium or Enterococcus faecalis with the MicroScan system (Dade International, MicroScan Inc., West Sacramento, Calif.) were further characterized by two supplementary biochemical tests (pigment production and motility). Twenty isolates (42%), all initially identified as E. faecium, were motile. Of these 20, 8 isolates (17%) produced yellow pigment and were identified as Enterococcus casseliflavus and the remaining 12 (25%) were nonpigmented and were identified as Enterococcus gallinarum. Identical identification results were obtained when PCR amplification of regions of the vanC gene was used as a technique for differentiating these organisms. The results of this study indicate that motility and pigment production tests together with commercial test systems are sufficient for reliable identifications of E. faecium, E. casseliflavus, and E. gallinarum.

PCR amplification of rRNA intergenic spacer regions as a method for epidemiologic typing of Clostridium difficile

From January to March 1993, a suspected outbreak of antibiotic-associated diarrhea occurred on a pediatric oncology ward of the Clinical Center Hospital at the National Institutes of Health. Isolates of Clostridium difficile obtained from six patients implicated in this outbreak were typed by both PCR amplification of rRNA intergenic spacer regions (PCR ribotyping) and restriction endonuclease analysis of genomic DNA. Comparable results were obtained with both methods; five of the six patients were infected with the same strain of C. difficile. Subsequent analysis of 102 C. difficile isolates obtained from symptomatic patients throughout the Clinical Center revealed the existence of 41 distinct and reproducible PCR ribotypes. These data suggest that PCR ribotyping provides a discriminatory, reproducible, and simple alternative to conventional molecular approaches for typing strains of C. difficile.

Improved enrichment broth for cultivation of fastidious organisms

An enrichment broth developed in our laboratory, fastidious broth (FB), was compared with two commercially available broth media, supplemented thioglycolate broth and enriched eugonic broth. FB supported the growth of a number of organisms that were not cultivatable in either of the other two media, including Corynebacterium jeikeium, Haemophilus influenzae, Neisseria gonorrhoeae, and Streptococcus pneumoniae. In addition, for several organisms that were able to grow in all three broths, including Neisseria meningitidis, Nocardia asteroides, and Actinomyces spp., both the time of incubation and the starting inoculum necessary to enable detection of growth were decreased significantly by using FB.

Rapid method for presumptive identification of Corynebacterium jeikeium

Corynebacterium jeikeium causes systemic infections, particularly in immunocompromised hosts. A minitube assay has been developed for the presumptive identification of C. jeikeium. With our rapid sucrose-urea test and conventional biochemical tests, sixty isolates of gram-positive, catalase-positive bacilli were identified in our laboratory. Results indicated that our assay has a sensitivity of 100% and a specificity of 90%.

Lysis-centrifugation blood cultures in the detection of tissue-proven invasive candidiasis. Disseminated versus single-organ infection

Several studies have demonstrated significantly higher frequency and more rapid detection of candidemia with blood culture methods performed by lysis-centrifugation (LC) in comparison with other techniques. Little is known, however, about the ability of LC blood culture methods to detect tissue-proven invasive candidiasis. We therefore investigated the sensitivity of LC blood cultures in the detection of tissue-proven invasive candidiasis. Between 1985 and 1991, invasive candidiasis was detected in 41 (5.1%) of 803 autopsies at the Clinical Center of the National Institutes of Health (Bethesda, MD, USA). Cases were classified as single-organ (SO) candidiasis (n = 20) and as disseminated candidiasis (DI) (n = 21). Patients with DI were more likely than those with SO to have a hematologic malignancy (71% vs 15%, P < 0.001) and to have gastrointestinal mucosal candidiasis (76% vs 25%, P = 0.003). LC detected fungemia in 16 (43%) of all 37 cases with blood cultures. When analyzed by classification, Candida spp. were isolated from blood in 11 (58%) of 19 patients with DI and in five (28%) of 18 patients with SO (P = 0.13). When analyzed by number of organs infected, blood cultures were positive in seven (78%) of nine patients with > 3 organs infected by Candida in comparison to five (28%) of 18 patients with one organ infected (P = 0.024). The mean recovery time for Candida in blood cultures was 2.6 days in DI and 3.2 days in SO (P = 0.017). There was no difference in colonies of organisms per LC tube between patients with DI and those with SO.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis of Pneumocystis carinii pneumonia by multiple lobe, site-directed bronchoalveolar lavage with immunofluorescent monoclonal antibody staining in human immunodeficiency virus-infected patients receiving aerosolized pentamidine chemoprophylaxis

The yields of both induced sputum examination and bronchoalveolar lavage (BAL) have been reported to be decreased for breakthrough episodes of Pneumocystis carinii pneumonia in human immunodeficiency virus-infected patients receiving aerosolized pentamidine chemoprophylaxis. This study assessed whether the yield of a single middle or lower lobe BAL could be increased by the utilization of two techniques: (1) indirect immunofluorescent staining with a combination of two murine monoclonal anti-Pneumocystis antibodies in addition to routine toluidine blue O and cytopathologic staining, and (2) the performance of multiple lobe, site-directed BAL (i.e., both upper lobe and middle or lower lobe lavage, including the lobe with the greatest radiographic abnormality). Results of 252 fiberoptic bronchoscopies performed at the National Institutes of Health and the Los Angeles County-University of Southern California Medical Center were analyzed. P. carinii pneumonia was documented in 21 episodes in patients who did not receive prior anti-Pneumocystis chemoprophylaxis and in 41 episodes in patients who received aerosolized pentamidine. Monoclonal antibody staining and multiple lobe, site-directed BAL resulted in similar diagnostic yields for P. carinii in the nonprophylaxis (100%) and aerosolized pentamidine (98%) groups. If BAL had been performed without monoclonal antibody staining and multiple lobe, site-directed lavage, then the yield would have decreased to 95% in the nonprophylaxis group and to 80% in the aerosolized pentamidine group.(ABSTRACT TRUNCATED AT 250 WORDS)

Pneumocystis carinii and specific fungi have a common epitope, identified by a monoclonal antibody

Because Pneumocystis carinii may be related to fungi, we evaluated the reactivities of monoclonal antibodies raised against P. carinii with a variety of fungi. Fifty-two fungi and six protozoa were evaluated by immunofluorescence. One of three monoclonal antibodies (MAbs) tested (MAb 7D7) reacted with 15 fungi but no protozoa. Saccharomyces cerevisiae showed the strongest reactivity by immunofluorescence. The reactive antigen was characterized for four fungi by the immunoblot technique. In all cases the antigen that was reactive with MAb 7D7 was larger than the P. carinii antigens that reacted with 7D7. In further studies with P. carinii, Aspergillus species, and S. cerevisiae, we found that MAb 7D7 reacted with a carbohydrate component in all organisms. The presence of an epitope that is common to P. carinii and a number of fungi further supports the fungal nature of P. carinii.

Optimal use of the cytocentrifuge for recovery and diagnosis of Pneumocystis carinii in bronchoalveolar lavage and sputum specimens

To facilitate the diagnosis of Pneumocystis carinii from bronchoalveolar lavage and sputum specimens, we have defined conditions for optimal use of the cytocentrifuge for this purpose. Centrifugation in the cytocentrifuge at 1,200 rpm for 10 min yielded the best recovery of P. carinii. To reliably ensure complete absorption of the fluid specimen from the cytocentrifuge chamber, it was necessary to use two absorption filters simultaneously. Different methods of treating induced sputum with mucolytic agents to process sputum with the cytocentrifuge were tried. Results of these studies and our current method for treating sputa are discussed. Comparisons of slides prepared by traditional centrifugation and by cytocentrifuge processing showed the latter to be equally effective for detecting P. carinii. The most prominent advantage of the cytocentrifuge was the much smaller area to review and consequently the shortened time required to read the slides.

Detection of Pneumocystis carinii by fluorescent-antibody stain using a combination of three monoclonal antibodies

A combination of three monoclonal antibodies, two prepared against human and one against rat Pneumocystis carinii, was used in an indirect fluorescent-antibody stain (IFA) to diagnose P. carinii in both bronchoalveolar lavage and lung biopsy specimens. This combination of monoclonal antibodies was specific for P. carinii and yielded bright fluorescence of both P. carinii cysts and trophozoites. A total of 126 specimens from 93 patients were stained for P. carinii by a toluidine blue O stain and the monoclonal IFA. Forty-five (35.7%) of these were positive for P. carinii by toluidine blue O, and 43 (34.1%) were positive by IFA. There was 98.4% agreement between both methods, with no false-positive and two false-negative occurrences by IFA. An IFA procedure with monoclonal antibodies such as those used in these studies can provide a simple, fast, and sensitive method for diagnosing P. carinii pneumonia by microbiology laboratories.

Medium for the simultaneous detection of pyocyanin and fluorescein pigments of Pseudomonas aeruginosa

To help simplify the identification of Pseudomonas aeruginosa by clinical microbiology laboratories, the authors developed a new medium, pyocyanin-fluorescein agar (PFA), which enhances the production of both Pseudomonas pigments simultaneously. Production of pigments on PFA was equivalent to production on a pyocyanin agar (P agar) and a fluorescein agar (F agar) used in combination and was superior to either P agar or F agar used alone. The medium is simple to prepare and it detected pigment in 94% of P. aeruginosa isolates tested.

Detection of Mycobacterium avium-Mycobacterium intracellulare in blood cultures using concentrated and unconcentrated blood in conjunction with a radiometric detection system

Studies were performed in order to determine optimal methods for isolating mycobacteria from blood. The combined use of a lysis-centrifugation (Isolator) system and a radiometric-detection system (Bactec) was compared to the use of either unconcentrated blood or centrifuged blood pellet in conjunction with the Bactec mycobacterial system. Results showed that for cultures with greater than 10 colony forming units (CFU) per ml of blood, the use of unconcentrated blood and centrifuged blood pellet was as sensitive as use of the Isolator concentrate. For cultures with lower colony counts (less than 10 CFU/ml), however, Isolator concentrate was consistently better than either centrifuged or unconcentrated blood. Since over half of our positive cultures had low colony counts, the use of Isolator concentrate inoculated into either a Bactec mycobacterial culture vial or onto Middlebrook agar slants is recommended over the use of either centrifuged blood pellet or unconcentrated blood inoculated into a Bactec mycobacterial culture vial.

Use of lysis-centrifugation (isolator) and radiometric (BACTEC) blood culture systems for the detection of mycobacteremia

Patients with acquired immune deficiency syndrome may develop infection with mycobacteria, particularly Mycobacterium avium-M. intracellulare (MAI). These infections can frequently be associated with demonstrable mycobacteremia with the organism. In this study, we compared the sensitivity of a radiometric (BACTEC system; Johnston Laboratories, Inc., Towson, Md.) liquid medium culture system with that of conventional solid mycobacterial culture media for cultures of blood from these patients. Both systems were inoculated with blood concentrate prepared by lysis-centrifugation (Isolator; Du Pont Co., Wilmington, Del.). Of 46 acquired immune deficiency syndrome patients whose blood was cultured, 28% had cultures positive for MAI. Patients had from less than 1 to more than 100 MAI colonies per ml of blood. Lowenstein-Jensen and Middlebrook 7H11 agars were comparable in recovery of MAI. BACTEC 12A vials containing double the standard volume of medium (4 ml) were more sensitive and were positive slightly earlier than vials containing the standard volume (2 ml). Conventional media detected 98% of positive cultures; BACTEC vials containing double volumes of medium detected 94% of positive cultures, whereas single-volume vials detected 77%. BACTEC vials were positive approximately 5 to 6 days sooner than slants or plates containing conventional media. For a few cultures, the use of unconcentrated blood was compared with the use of Isolator-concentrated blood by using each of these as inocula for BACTEC vials. Results for these cultures suggested that, although the use of Isolator-concentrated blood resulted in greater sensitivity than the use of unconcentrated blood would, the use of unconcentrated blood would still result in the detection of at least 78% of positive cultures.

Comparison of lysis-centrifugation with lysis-filtration and a conventional unvented bottle for blood cultures

Evaluation of a commercially available lysis-centrifugation blood culture system (Isolator, DuPont Co., Wilmington, Del.) and a lysis-filtration blood culture system for 3,111 cultures showed that both methods had comparable recoveries (73 and 68%, respectively) of significant aerobic and facultatively anaerobic isolates. The unvented conventional blood culture bottle had a recovery rate of 59%. Although the lysis-centrifugation and lysis-filtration systems had comparable recoveries of pathogens, the lysis-centrifugation system had the advantage of having colonies immediately available for further testing. The contamination rate with the lysis-centrifugation system was 3%, compared with 6% with the lysis-filtration system and 0.4% with brain heart infusion.