Argatroban anticoagulant therapy in patients with heparin-induced thrombocytopenia.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is an immune-mediated syndrome caused by heparin. Complications range from thrombocytopenia to thrombocytopenia with thrombosis. We report a prospective, historical- controlled study evaluating the efficacy and safety of argatroban, a direct thrombin inhibitor, as anticoagulant therapy in patients with HIT or HIT with thrombosis syndrome (HITTS). METHODS AND RESULTS: Patients with HIT (isolated thrombocytopenia, n=160) or HITTS (n=144) received 2 microgram. kg(-1). min(-1) IV argatroban, adjusted to maintain the activated partial thromboplastin time 1.5 to 3.0 times baseline value. Treatment was maintained for 6 days, on average. Clinical outcomes over 37 days were compared with those of 193 historical control subjects with HIT (n=147) or HITTS (n=46). The incidence of the primary efficacy end point, a composite of all-cause death, all-cause amputation, or new thrombosis, was reduced significantly in argatroban-treated patients versus control subjects with HIT (25.6% versus 38.8%, P=0.014). In HITTS, the composite incidence in argatroban-treated patients was 43.8% versus 56.5% in control subjects (P=0.13). Significant between-group differences by time-to-event analysis of the composite end point favored argatroban treatment in HIT (P=0.010) and HITTS (P=0.014). Argatroban therapy, relative to control subjects, also significantly reduced new thrombosis and death caused by thrombosis (P<0.05). Argatroban-treated patients achieved therapeutic activated partial thromboplastin times generally within 4 to 5 hours of starting therapy and, compared with control subjects, had a significantly more rapid rise in platelet counts (P=0.0001). Bleeding events were similar between groups. CONCLUSIONS: Argatroban anticoagulation, compared with historical control subjects, improves clinical outcomes in patients who have heparin-induced thrombocytopenia, without increasing bleeding risk.

Safety of warfarin anticoagulation in patients with heparin-induced thrombocytopenia.

OBJECTIVES: Venous limb gangrene has been reported to occur after high warfarin doses in heparin-induced thrombocytopenia (HIT), and this observation has been used to exclude warfarin management in this condition. The outcome of patients receiving modest doses of warfarin was studied. DESIGN: Retrospective study of 114 consecutive HIT patients who received diagnoses by platelet aggregometry; 51 of the 114 patients received warfarin. SETTING: Tertiary-care medical center. RESULTS: Thirty-five patients received warfarin for non-HIT indications, and 16 received warfarin for heparin-associated thrombosis. Warfarin was given to 23 patients (47%) 2.4 +/- 0.4 days prior to the onset of HIT, in 19 while receiving IV heparin for an overlap of 2.7 +/- 0.4 days. Twenty-eight patients (53%) received warfarin 2.8 +/- 1.0 days after the diagnosis of HIT. Patients received 11 +/- 1 doses of warfarin over 16 +/- 2 days, with a mean daily dose of 3.5 +/- 0.5 and a maximum dose of 9 +/- 0.5 mg. Prothrombin time at discharge was 17.3 +/- 0.4 s with a maximum of 22.8 +/- 0.8. The final international normalized ratio was 2.9 +/- 0. 3, and the maximum was 7.5 +/- 1.4. The minimum therapeutic range was reached in 59% of determinations. When compared to the 63 patients who did not receive warfarin, warfarin patients received more IV heparin (86% vs 41%; p < 0.001), open heart surgery (78% vs 43%; p < 0.001), and had a lower mortality (8% vs 43%; p < 0.001), but had no differences in thrombosis. CONCLUSIONS: Modest doses of warfarin were not associated with a worse outcome in patients with HIT.

Molecular mechanisms of holoprosencephaly.

Holoprosencephaly (HPE) is the most common developmental defect of the forebrain in humans. Several distinct human genes for holoprosencephaly have now been identified. They include Sonic hedgehog (SHH), ZIC2, and SIX3. Many additional genes involved in forebrain development are rapidly being cloned and characterized in model vertebrate organisms. These include Patched (Ptc), Smoothened (Smo), cubitus interuptus (ci)/Gli, wingless (wg/Wnt, decapentaplegic (dpp)/BMP, Hedgehog interacting protein (Hip), nodal, Smads, One-eyed pinhead (Oep), and TG-Interacting Factor (TGIF). However, further analysis is needed before their roles in HPE can be established. Here we present an overview of the presently known genes causing human holoprosencephaly and describe candidate genes involved in forebrain development identified in other systems. A model is discussed for how these genes may interact within and between several different signaling pathways to direct the formation of the forebrain.

Failure of early heparin cessation as treatment for heparin-induced thrombocytopenia.

PURPOSE: The complications of heparin-induced thrombocytopenia include thrombosis and death. The purpose of the study was to determine whether early heparin cessation can prevent these outcomes. SUBJECTS AND METHODS: We performed a retrospective analysis of consecutive patients with heparin-induced thrombocytopenia diagnosed by platelet aggregometry. Demographic, clinical, and laboratory findings were compared in patients by whether heparin treatment was stopped early (< or = 48 hours) or late (>48 hours) after the onset of thrombocytopenia, as well as between patients with and without thrombosis. Thrombocytopenia was defined as a 50% decline in baseline platelet counts or an absolute platelet count < 100,000/mm3. RESULTS: Of the 113 patients, 38% developed thrombosis and 27% died. One-half of patients had thrombosis diagnosed >24 hours after heparin cessation. No difference in thrombosis or mortality was found in the 40 patients with early heparin cessation [mean (+/-SD) time of cessation 0.7 +/- 0.6 days] compared with the 73 patients with late heparin cessation (5 +/- 3 days). Thrombosis >24 hours after heparin cessation occurred in 61% of the patients in the early group and in 40% of the late group (P = 0.17). In a multivariate analysis, only a lower nadir of the platelet count (percent of baseline) was associated with thrombosis. Neither thrombosis nor the time to heparin cessation were associated with mortality. CONCLUSIONS: Early heparin cessation was not effective in reducing morbid events in patients with heparin-induced thrombocytopenia. Treatment strategies other than heparin cessation alone should be considered in patients with this condition.

Mutations in the homeodomain of the human SIX3 gene cause holoprosencephaly.

Holoprosencephaly (HPE) is a common, severe malformation of the brain that involves separation of the central nervous system into left and right halves. Mild HPE can consist of signs such as a single central incisor, hypotelorism, microcephaly, or other craniofacial findings that can be present with or without associated brain malformations. The aetiology of HPE is extremely heterogeneous, with the proposed participation of a minimum of 12 HPE-associated genetic loci as well as the causal involvement of specific teratogens acting at the earliest stages of neurulation. The HPE2 locus was recently characterized as a 1-Mb interval on human chromosome 2p21 that contained a gene associated with HPE. A minimal critical region was defined by a set of six overlapping deletions and three clustered translocations in HPE patients. We describe here the isolation and characterization of the human homeobox-containing SIX3 gene from the HPE2 minimal critical region (MCR). We show that at least 2 of the HPE-associated translocation breakpoints in 2p21 are less than 200 kb from the 5' end of SIX3. Mutational analysis has identified four different mutations in the homeodomain of SIX3 that are predicted to interfere with transcriptional activation and are associated with HPE. We propose that SIX3 is the HPE2 gene, essential for the development of the anterior neural plate and eye in humans.

Failure of current strategies in the prevention of thrombosis in patients with heparin-induced thrombocytopenia: a clinician's perspective.

Heparin-induced thrombocytopenia (HIT), and heparin-induced thrombocytopenia with thrombosis syndrome (HITTS), are immune-mediated complications of heparin therapy associated with significant morbidity and mortality. Although much has been learned about the pathophysiology of this syndrome, there are many difficult issues remaining for physicians involved in the daily care of the patient about the diagnosis, prevention, and treatment. To determine whether the earliest detection of HIT and heparin cessation impacted outcome, 116 consecutive patients at a single institution, with HIT diagnosed by platelet aggregometry, were divided into groups by time to heparin cessation based on daily platelet counts. Thrombocytopenia was defined in two ways: as a 50% decline from baseline and an absolute platelet count of less than 100x10(9)/L. The overall thrombosis rate was 39% and was predominantly venous. The mortality rate of 27% was similar in patients with both HIT and HITTS. Despite heparin cessation at less than 48 h from the onset of thrombocytopenia (mean 0.5 days), there were no differences in thrombosis or mortality when compared to patients with later heparin cessation (mean 4.3 days). In summary, early detection of HIT with heparin cessation is insufficient therapy for the management and treatment of HITTS. An alternative to this strategy in the treatment of patients with HIT is indicated.

Coagulation laboratory testing in patients treated with argatroban.

During clinical trials with the thrombin inhibitor argatroban, appropriate methods for drug monitoring were identified. Treated patients presented interesting challenges for coagulation laboratory parameter testing in the presence of argatroban. These issues are reported here. Regarding the monitoring of argatroban, the aPTT and ACT were effectively used clinically for low (0-2.5 microg/mL) or high (1-15 microg/mL) doses of argatroban. However, system (reagent and instrument) differences were noted in the time-to-clot values. A clot-based assay using Ecarin as the activator (ECT, Ecarin clotting time) appeared to be useful for monitoring both low and high drug levels with less interference from other drugs or coagulation defects. Also identified were the chromogenic antithrombin assay that could directly quantify argatroban and an HPLC based assay that could specifically quantify argatroban and its metabolites. With regard to assay interference by argatroban, several important effects were observed. The presence of argatroban synergistically interfered with the INR for those patients treated with oral anticoagulants. However, a chromogenic based method was able to determine factor X levels as a monitor of the oral anticoagulation without effect from argatroban. A similar synergistic response on the aPTT with heparin and argatroban was observed. Patients receiving argatroban evaluated for potential coagulation abnormalities could not be tested with the routine functional (clot based) assays for fibrinogen, factor levels or protein C. Argatroban acted as an inhibitor in these assays, causing a dose-dependent false decrease of fibrinogen and factor levels, and a false increase of protein C. Using a chromogenic assay for protein C, values equal to those obtained by an immunologic assay were achieved. These issues will most likely hold true for all thrombin inhibitors.

Clinical experience with combined treatment of thrombin inhibitors and GPIIb/IIIa inhibitors in patients with HIT.

Despite the use of potent anticoagulants such as r-hirudin and argatroban, the morbidity/mortality of heparin-induced thrombocytopenia (HIT) patients remains high. In the last several months, we have treated three HIT-positive patients with a combined therapy of thrombin inhibitor and GPIIb/IIIa inhibitor when treatment with thrombin inhibitor alone failed to alleviate acute thrombosis. Combination therapies included r-hirudin (Refludan) with tirofiban (Aggrastat) or argatroban (Novastan) with ReoPro. A reduced dose of the thrombin inhibitor with the standard dose of the antiplatelet drug was the dosing regimen used. In all cases, there was no overt bleeding that required intervention and all patients had improved or fully recovered. This first report of the use of GPIIb/IIIa inhibitors with thrombin inhibitors in HIT patients with active thrombosis suggests that this combined therapy may be more effective than thrombin inhibitor treatment alone. The data from these three cases warrant testing of this therapeutic regimen in larger studies to determine optimal dosing strategies.

Inadequacy of current prevention strategies for heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia is one of the most difficult problems facing clinicians today. Despite recent understanding of the pathophysiology of this disorder, there are many unresolved issues about diagnosis, prevention, and treatment. In this article, difficulties physicians encounter when faced with a suspected heparin-induced thrombocytopenia patient will be reviewed as well as our experience in 113 patients with heparin-induced thrombocytopenia which highlights the failure of current preventive strategies for heparin-induced thrombocytopenia. The experience of using warfarin in 51 patients with heparin-induced thrombocytopenia will also be reviewed.

Transesophageal echocardiographic assessment of systolic mitral leaflet displacement among patients with mitral valve prolapse.

Though qualitative transthoracic echocardiographic criteria for abnormal systolic leaflet motion are widely accepted as diagnostic characteristics of mitral valve prolapse, transesophageal echocardiographic criteria have not been evaluated against such a standard. Because transesophageal imaging planes are not identical to transthoracic imaging planes, validation of transesophageal echocardiographic criteria for mitral valve prolapse is needed. Eleven patients with mitral valve prolapse (based on physical findings and transthoracic echocardiographic criteria) and 11 healthy persons underwent prospective transesophageal echocardiography in two orthogonal imaging planes. Measurements of maximal leaflet displacement superior to the annular hinge points and mitral prolapse area subtended by the displaced mitral leaflets and the chord connecting the annular hinge points were performed in triplicate and averaged by a blinded observer. Though maximal systolic leaflet displacement was greater among patients with mitral valve prolapse than healthy subjects for both the transesophageal four-chamber (0.66+/-0.39 cm versus 0.05+/-0.11 cm, p < 0.001) and two chamber views (0.57+/-0.44 cm versus 0.20+/-0.25 cm, p < 0.04), no unique value differentiated patients with from those without mitral valve prolapse. Mitral prolapse area was greater for patients with mitral valve prolapse than for healthy subjects in both transesophageal four-chamber (1.23+/-1.18 cm2 versus 0.03+/-0.06 cm2, p < 0.02) and two-chamber views (1.73+/-1.65 cm2 versus 0.21+/-0.31 cm2, p < 0.02). Whereas a mitral prolapse area of 0.20 cm2 uniquely differentiated patients with from those without mitral valve prolapse in the four-chamber view, data overlap prevented determination of a similar diagnostic criterion for the two-chamber view. The difficulty in defining quantitative transesophageal echocardiographic criteria for mitral valve prolapse based on leaflet displacement alone suggested that the simple qualitative observation of leaflet displacement above the annular hinge points should not be used as a defining morphologic criterion for mitral valve prolapse.

Anticoagulation with Novastan (argatroban) in patients with heparin-induced thrombocytopenia and heparin-induced thrombocytopenia and thrombosis syndrome.

Heparin-induced thrombocytopenia (HIT) is a syndrome that has been identified with increased frequency. The mortality associated with HIT approaches 35%. Previous strategies for treatment of the associated thrombosis with HIT have frustrated clinicians with poor outcomes. Recent awareness of the complex pathophysiology of HIT combined with the availability of new anticoagulants has led to the development of a rational therapeutic strategy for this group of patients. The foundation of this strategy involves thrombin inhibition and careful patient monitoring. Our preliminary results with the thrombin inhibitor argatroban (Novastan) have been favorable and warrant continued investigation.

Transesophageal echocardiographic assessment of the contribution of intrinsic tissue thickness to the appearance of a thick mitral valve in patients with mitral valve prolapse.

OBJECTIVES: This prospective, blinded transesophageal echocardiographic study was performed to determine the relative contributions of leaflet redundancy and overlap versus intrinsic tissue thickening as mechanisms for the apparent increase in diastolic thickness of the mitral valve. BACKGROUND: Increased diastolic thickness of the mitral valve has been identified as an echocardiographic feature that predicts subsequent adverse sequelae in patients with mitral valve prolapse (MVP). METHODS: Eleven patients with clinical and transthoracic echocardiographic evidence of MVP and 11 age-matched control subjects underwent protocol transesophageal echocardiography to image the mitral valve in two orthogonal planes and to measure its thickness in systole and diastole. RESULTS: Maximal diastolic width of the slack, unloaded anterior leaflet was significantly greater in patients with MVP than in control subjects (mean +/- SD: 0.64 +/- 0.20 cm vs. 0.30 +/- 0.04 cm, p < 0.001). Similarly, diastolic posterior leaflet width was greater in patients with MVP (0.67 +/- 0.39 cm vs. 0.31 +/- 0.06 cm, p < 0.01). In contrast, minimal systolic width of the distended pressure-loaded mitral valve was not significantly different between patients with MVP and control subjects for either the anterior (0.22 +/- 0.05 cm vs. 0.20 +/- 0.04 cm, p = NS) or the posterior (0.25 +/- 0.07 cm vs. 0.24 +/- 0.05 cm, p = NS) leaflets. The percent change in leaflet width from diastole to systole (% delta W), an index of the contribution of dynamic factors (e.g., leaflet redundancy and overlap) to the apparent increase in diastolic leaflet thickness, was significantly greater in patients with MVP than in control subjects for both the anterior (% delta W 62 +/- 13% vs. 34 +/- 16%, p < 0.001) and the posterior (% delta W 54 +/- 19% vs. 22 +/- 21%, p < 0.005) leaflets. CONCLUSIONS: The apparent increase in diastolic mitral leaflet thickness in patients with MVP versus control subjects is largely attributable to dynamic factors such as leaflet redundancy, overlap and deformation. During diastole, when the mitral leaflets are slack and unstressed, the leaflets appear markedly thickened in patients with MVP. In contrast, during systole, when developed intraventricular pressure distends the leaflets, causing them to stretch and balloon into the left atrium, the intrinsic tissue thickness is much less than that measured in diastole. These findings have important implications for the morphologic criteria used to diagnose MVP and the potential pathophysiologic mechanisms for adverse sequelae in this syndrome.

Comparison of polymerase chain reaction and microbiological culture for detection of salmonellae in equine feces and environmental samples.

OBJECTIVE: To compare the sensitivity of polymerase chain reaction (PCR) with microbiological culture for detecting salmonellae in equine fecal samples and equine environmental swab specimens. DESIGN: Samples and specimens were tested by PCR and microbiological culture. SAMPLE POPULATION: A fecal sample from each of 152 horses admitted consecutively to the clinic for evaluation by the outpatient service, 282 fecal samples from 110 hospitalized horses that had been submitted to the clinical microbiology laboratory, and 313 environmental swab specimens were examined. PROCEDURE: Each sample and specimen in the study was tested, using PCR and microbiological culture. Results of PCR and culture were compared. RESULTS: Significantly (P < 0.001) more fecal samples were positive by PCR than by microbiological culture. 26 of 152 (17.1%) fecal samples collected from horses admitted by the outpatient service were positive by PCR and none was positive by culture. 71 of 110 hospitalized horses were identified as positive by PCR, compared with 11 horses identified as positive by culture. All culture-positive horses were positive by PCR. Of the 11 culture-positive horses, 10 (90.9%) were identified as PCR positive after testing of the first sample submitted, compared with 7 (63.6%) by culture. All PCR-positive horses were detected after a total of 3 samples/horse were submitted, whereas as many as 5 samples/horse was required to identify all culture-positive horses. 8 of 313 environmental specimens were positive by PCR, and none was positive by culture. CONCLUSION: The PCR method reported here was more sensitive, more rapid, and required submission of fewer samples or specimens than did microbiological culture for detecting salmonellae.

Production of neocollagen by cells invading hydrogel sponges implanted in the rabbit cornea.

BACKGROUND: Poly(2-hydroxyethyl methacrylate) sponges are artificial tissue-equivalent matrices with potential value as materials for the peripheral zone of artificial corneas. A keratoprosthetic device was developed incorporating a poly(HEMA) spongy skirt which allowed cellular invasion. The present in vivo study investigated the biosynthetic activity of stromal fibroblasts growing within a poly(HEMA) sponge implanted into the rabbit cornea. METHODS: A porous poly(HEMA) hydrogel was synthesized by polymerization in a large excess of water. Specimens with a pore size larger than 10 microns were impregnated with collagen type I and then implanted into the limbal region of cornea in four rabbits. The animals were followed clinically for 28 days, when they were anaesthetized and new sponge specimens were implanted in their second eye. After 2 h, both eyes were enucleated. The 28-day and 2-h explants were subjected to autoradiographic analysis following labelling with tritiated proline and to an immunostaining technique using antibodies to collagen types I-VI. RESULTS: The autoradiographic analysis showed that the fibroblasts within the 28-day explants continued to be synthetically active and deposited proteins. Using the immunostaining technique, the deposition was most clearly demonstrated by the localization of collagen type III in the tissue invading the sponge. Both techniques failed to indicate any cellular activity in the short-time implants. CONCLUSIONS: The presence of collagen type III is consistent with a normal healing response of the stromal fibroblasts and indicates that poly(-HEMA) sponges are able to function as tissue-equivalent matrices.

Detection of Salmonella enteritidis in equine feces using the polymerase chain reaction and genus-specific oligonucleotide primers.

Salmonella was identified in feces from horses, using the polymerase chain reaction (PCR) and genus-specific oligonucleotide primers. Feces from healthy horses were determined to be culture negative and PCR negative for Salmonella. Fecal samples were inoculated with known numbers of colony-forming units (CFU) of S. enteritidis. The fecal samples were enriched overnight in tetrathionate broth, and then DNA was extracted and amplified by PCR using genus-specific primers. Sensitivity of the assay extended to 10 degrees CFU Salmonella enteritidis/g feces; sensitivity of microbiologic culture with enrichment extended to 10 degrees CFU Salmonella enteritidis/g feces. Feces that were not inoculated with S. enteritidis were negative by the PCR. Detection of salmonellae in feces was possible using the PCR within 24 hours from the time of submission of samples. Because samples were enriched, isolates were available for determining antibiograms and serologic grouping or typing.

Comparison of the polymerase chain reaction using genus-specific oligonucleotide primers and microbiologic culture for the detection of Salmonella in drag-swabs from poultry houses.

Drag-swab samples were collected from 18 poultry houses at 9 broiler farms. Fifty drag-swab samples were tested for Salmonella by microbiologic culture using selective enrichment and the polymerase chain reaction (PCR) with oligonucleotide primers specific for all members of the genus Salmonella. Drag-swab samples were tested for Salmonella using PCR before and after enrichment. Only one sample was positive by PCR prior to enrichment. Forty-seven of the drag-swabs samples tested after enrichment were positive for Salmonella using PCR, and 29 were positive by microbiologic culture. All but one of the culture-positive samples were positive by PCR; this discordant sample was classified as indeterminate by PCR. Salmonella was identified in houses from all nine farms by PCR and eight of nine farms by microbiologic culture. Salmonella was found in all 18 houses by PCR and in 15 of 18 houses by microbiologic culture. In this study, PCR was significantly (P < .001) more sensitive than culture for environmental monitoring of Salmonella using drag-swabs.

Genus-specific detection of salmonellae in equine feces by use of the polymerase chain reaction.

Members of the genus Salmonella were identified in feces from horses, using the polymerase chain reaction (PCR) and genus-specific oligonucleotide primers. Feces from healthy horses were determined to be culture-negative for Salmonella spp. Fecal samples were inoculated with known numbers of colony-forming units (CFU) of S anatum, S derby, S enteritidis, S heidelberg, S newport, and S typhimurium. The DNA was extracted from fecal samples and amplified by PCR, using genus-specific primers. Sensitivity of the assay extended to 10(3) CFU of Salmonella sp/g of feces; sensitivity of microbiologic culture with enrichment extended to 10(2) CFU of Salmonella sp/g of feces. Feces that were not inoculated with Salmonella spp were negative by the PCR. Detection of Salmonellae in feces was possible, using the PCR, within 10 to 12 hours from the time of submission of samples.

Significance of electrocardiographic ST elevation during coronary artery bypass surgery.

The aim of this study was to determine the significance of new electrocardiographic (ECG) ST elevation during coronary artery bypass surgery. Multilead ECGs were recorded intraoperatively approximately every 3 min on 105 patients. Cases of new ST elevation were divided into ischemic and those considered to be due to nonischemic causes such as cooling during cardiopulmonary bypass (CPB), defibrillation, new cardiac conduction abnormalities, and pericarditis. The myocardial fraction of creatine kinase (CK-MB) > or = 25 IU/L was considered to be indicative of myocardial injury. Both patients who had ischemic ST elevation prior to CPB and all seven patients who had ST elevation in temporal association with the administration of protamine had peak CK-MB > or = 25 IU/L. One patient with peak CK-MB > or = 25 IU/L did not have ST elevation and was considered to have injury during CPB. Two of these ten patients had Q wave myocardial infarctions (MIs). For the detection of patients with peak CK-MB > or = 25 IU/L, the sensitivity of ischemic ST elevation was 90% and the specificity was 100%. A history of MI prior to surgery and a history of Type I diabetes were associated with peak CK-MB > or = 25 IU/L (P < 0.05).

Detection of Salmonella enteritidis in feces from poultry using booster polymerase chain reaction and oligonucleotide primers specific for all members of the genus Salmonella.

Salmonella enteritidis was identified in feces from hens using the polymerase chain reaction (PCR) and oligonucleotide primers specific for all members of the genus Salmonella. Feces from specific-pathogen-free Leghorn hens were determined to be negative for Salmonella by microbiological culture and by the PCR. Fecal samples were inoculated with known numbers of colony-forming units of S. enteritidis. The DNA was extracted from fecal samples and amplified by the PCR using genus-specific primers. Salmonella were detected in all samples known to be positive; the sensitivity of the assay extended to 1 cfu of S. enteritidis/g feces. Feces that were not inoculated with Salmonella were negative. Microbiological culture was less sensitive than the PCR assay; results of culture of feces with less than 10(2) cfu/g were negative. Although S. enteritidis was used in this study, the oligonucleotide primers used in this study have been previously demonstrated to be genus-specific for Salmonella.