Kirk A. Easley

Age- and gender-related changes in the cellularity of human bone marrow and the prevalence of osteoblastic progenitors.

Bone marrow harvested by aspiration contains connective tissue progenitor cells which can be induced to express a bone phenotype in vitro. The number of osteoblastic progenitors can be estimated by counting the colony‐forming units which express alkaline phosphatase (CFU‐APs). This study was undertaken to test the hypothesis that human aging is associated with a significant change in the number or prevalence of osteoblastic progenitors in the bone marrow. Four 2‐ml bone marrow aspirates were harvested bilaterally from the anterior iliac crest of 57 patients, 31 men (age 15–83) and 26 women (age 13–79). A mean of 64 million nucleated cells was harvested per aspirate. The mean prevalence of CFU‐APs was found to be 55 per million nucleated cells. These data revealed a significant age‐related decline in the number of nucleated cells harvested per aspirate for both men and women (P = 0.002). The number of CFU‐APs harvested per aspirate also decreased significantly with age for women (P = 0.02), but not for men (P = 0.3). These findings are relevant to the harvest of bone marrow derived connective tissue progenitors for bone grafting and other tissue engineering applications, and may also be relevant to the pathophysiology of age‐related bone loss and post‐menopausal osteoporosis.

Aspiration to Obtain Osteoblast Progenitor Cells from Human Bone Marrow: The Influence of Aspiration Volume*

Bone marrow contains osteoblast progenitor cells that can be obtained with aspiration and appear to arise from a population of pluripotential connective-tissue stem cells. When cultured in vitro under conditions that promote an osteoblastic phenotype, osteoblast progenitor cells proliferate to form colonies of cells that express alkaline phosphatase and, subsequently, a mature osteoblastic phenotype. We evaluated the number of nucleated cells in bone-marrow samples obtained with aspiration from the anterior iliac crest of thirty-two patients without systemic disease. There were nineteen male patients and thirteen female patients; the mean age was forty-one years (range, fourteen to seventy-seven years). The prevalence and concentration of the osteoblast progenitor cells also were determined, by placing the bone-marrow-derived cells into tissue-culture medium and counting the number of alkaline phosphatase-positive colony-forming units. In order to assess the effect of aspiration volume, two sequential experiments were performed. In the first experiment, aspiration volumes of one and two milliliters were compared. In the second experiment, aspiration volumes of two and four milliliters were compared. The mean prevalence of alkaline phosphatase-positive colony-forming units in the bone-marrow samples was thirty-six per one million nucleated cells (95 per cent confidence interval, 28 to 47); a mean of 2400 alkaline phosphatase-positive colony-forming units was obtained from a two-milliliter aspirate. There was a significant difference among the patients with respect to the number of alkaline phosphatase-positive colony-forming units in these bone-marrow samples (p < 0.001). Seventy per cent of this variation in the prevalence was due to variation among patients, and 20 per cent was due to variation among aspirates. The number of alkaline phosphatase-positive colony-forming units in the aspirate increased as the aspiration volume increased. However, contamination by peripheral blood also increased as the aspiration volume increased. An increase in the aspiration volume from one to four milliliters caused a decrease of approximately 50 per cent in the final concentration of alkaline phosphatase-positive colony-forming units in an average sample. CLINICAL RELEVANCE: On the basis of these data, we recommend that, when bone marrow is obtained with aspiration for use as a bone graft, the volume of aspiration from any one site should not be greater than two milliliters. A larger volume decreases the concentration of osteoblast progenitor cells because of dilution of the bone-marrow sample with peripheral blood. We estimate that four one-milliliter aspirates will provide almost twice the number of alkaline phosphatase-positive colony-forming units as will one four-milliliter aspirate. In addition, these data confirm that humans differ significantly from one another with respect to the cellularity of bone marrow and the prevalence of osteoblast progenitor cells. Additional studies are necessary to determine if the number or prevalence of alkaline phosphatase-positive colony-forming units in bone marrow is a determining factor in the efficacy of an autogenous bone or bone-marrow graft and to ascertain how the number and function of alkaline phosphatase-positive colony-forming units may change as a function of factors such as age, menopausal status, and selected diseases.

The seroprevalence of cagA-positive Helicobacter pylori strains in the spectrum of gastroesophageal reflux disease

BACKGROUND & AIMS The role of Helicobacter pylori in the pathogenesis of gastroesophageal reflux disease (GERD) is unknown. We determined the prevalence of cagA-positive (cagA+) H. pylori strains in patients with GERD or its complications compared with controls of similar age. METHODS A total of 153 consecutive patients with GERD, Barretts esophagus, and Barretts esophagus complicated by dysplasia or adenocarcinoma were compared with 57 controls who underwent upper endoscopy for reasons other than GERD. H. pylori infection and CagA antibody status were determined by histology and enzyme-linked immunosorbent assay. RESULTS H. pylori prevalence was lower (34%) in patients with GERD and its sequelae than in the control group (45.6%)(P = 0.15). Regardless of the group, increasing age was associated with higher prevalence of H. pylori (P = 0.003). When compared with controls (42.3%), the prevalence of cagA+ H. pylori strains decreased (P = 0.008) in patients with more severe complications of GERD (GERD, 36.7% [nonerosive GERD, 41.2%; erosive GERD, 30.8%]; Barretts esophagus, 13.3%; and Barretts with adenocarcinoma/dysplasia, 0%). CONCLUSIONS Prevalence of H. pylori in patients with GERD and its sequelae was lower but not significantly different than that of a control group. However, patients carrying cagA+ strains of H. pylori may be protected against the complications of GERD, especially Barretts esophagus and its associated dysplasia and adenocarcinoma.

Vertebral Osteomyelitis: Long-Term Outcome for 253 Patients from 7 Cleveland-Area Hospitals

We report a retrospective study of 253 patients with vertebral osteomyelitis (VO) who had long-term follow-up. Eleven percent of the patients died, residual disability occurred in more than one-third of the survivors, and relapse occurred in 14%. Median duration of follow-up was 6.5 years (range, 2 days to 38 years). Independent risk factors for adverse outcome (death or qualified recovery) were neurologic compromise, time to diagnosis, and hospital acquisition of infection (P< or =.004). Surgical treatment resulted in recovery or improvement in 86 (79%) of 109 patients. Magnetic resonance images (110 patients) were often obtained late in the course of infection and did not significantly affect outcome. Often, relapse developed in individuals with severe vertebral destruction and abscesses, appearing some time after surgical drainage or debridement. Recurrent bacteremia, paravertebral abscesses, and chronically draining sinuses were independently associated with relapse (P< or =.001). An optimal outcome of VO requires heightened awareness, early diagnosis, prompt identification of pathogens, reversal of complications, and prolonged antimicrobial therapy.

Clinical patterns, natural history, and progression of ulcerative colitis : a long-term follow-up of 1116 patients

We studied the natural history of ulcerative colitis (UC) by following 1116 patients in whom UC had been diagnosed or confirmed at The Cleveland Clinic Foundation between 1960 and 1983. Data before 1973 were obtained retrospectively. Criteria for inclusion in the study were: a diagnosis of UC confirmed by clinical, radiographic, endoscopic, and histologic examination; disease location that could be defined as one of three categories (proctosigmoiditis, pancolitis, or left-sided colitis); and a follow-up of at least five years (mean=12.7 years). Mean age at diagnosis was 32 years. Of the 1116 patients, 46.2% (516) had proctosigmoiditis; 36.7% (410) had pancolitis (colitis of the entire large intestine); and 17.0% (190) had left-sided colitis (from the dentate line to the splenic flexure). Early complications (within two years of diagnosis) included colonic hemorrhage (16.7%) and toxic colitis (12.7%). Complications were highest among patients with pancolitis. Surgery was required for 37.6% of the patients. Primary indications for surgery included chronic or intractable disability (40.2%), fulminating medical failure (16.9%), and colonic dilatation (18.4%). At the most recent follow-up, the disease had extended (progressed to a more serious category) in 53.8% of the patients, although 67.2% were asymptomatic and only 37.0% were on medications. Both the final disease destination and the initial diagnosis impacted cumulative colectomy-ileostomy rates. Factors associated with extension were toxic colitis (P<0.0001); extent of disease at diagnosis (P<0.0001); joint symptoms (P=0.0008); younger age at diagnosis (P=0.06); and severe bleeding (P=0.07).

Correlation between ammonia levels and the severity of hepatic encephalopathy

PURPOSE Because the correlation between ammonia levels and the severity of hepatic encephalopathy remains controversial, we prospectively evaluated the correlation in 121 consecutive patients with cirrhosis. METHODS The diagnosis of hepatic encephalopathy was based on clinical criteria, and the severity of hepatic encephalopathy was based on the West Haven Criteria for grading of mental status. Arterial and venous blood samples were obtained from each patient. Four types of ammonia measurements were analyzed: arterial and venous total ammonia, and arterial and venous partial pressure of ammonia. Spearman rank correlations (r(s)) were calculated. RESULTS Of the 121 patients, 30 (25%) had grade 0 encephalopathy (no signs or symptoms), 27 (22%) had grade 1, 23 (19%) had grade 2, 28 (23%) had grade 3, and 13 (11%) had grade 4 (the most severe signs and symptoms). Each of the four measures of ammonia increased with the severity of hepatic encephalopathy: arterial total ammonia (r(s) = 0.61, P < or = 0.001), venous total ammonia (r(s) = 0.56, P < or = 0.001), arterial partial pressure of ammonia (r(s) = 0.55, P < or = 0.001), and venous partial pressure of ammonia (r(s) = 0.52, P < or = 0.001). CONCLUSION Ammonia levels correlate with the severity of hepatic encephalopathy. Venous sampling is adequate for ammonia measurement. There appears to be no additional advantage of measuring the partial pressure of ammonia compared with total ammonia levels.

Inflammation and intestinal metaplasia of the gastric cardia: The role of gastroesophageal reflux and H. pylori infection

BACKGROUND & AIMS Whether inflammation of the cardia indicates gastroesophageal reflux disease (GERD) and/or is a manifestation of pangastritis caused by Helicobacter pylori infection is unknown. The aim of this study was to evaluate the relationship between cardia inflammation, H. pylori infection, and cardia intestinal metaplasia in patients with and without GERD. METHODS Patients with GERD were compared with controls undergoing endoscopy for a variety of other conditions. Endoscopic biopsy specimens from the distal esophagus and cardia, fundus, and antrum were evaluated for inflammation, H. pylori infection, and intestinal metaplasia. RESULTS Neither the prevalence of H. pylori infection (controls, 48%; GERD, 41%) nor cardia inflammation (controls, 41%; GERD, 40%) differed between groups. All 11 controls and 22 of 23 patients with GERD (96%) and cardia inflammation had H. pylori infection. Esophagitis was more common among GERD patients (33%) than controls (7%; P = 0.01). Cardia intestinal metaplasia was more common among controls (22%) than GERD patients (3%; P = 0.01); all had cardia inflammation, 7 had H. pylori infection, and 6 had metaplasia elsewhere in the stomach. CONCLUSIONS The prevalence of cardia inflammation is similar in patients with and without GERD and is associated with H. pylori infection (P < 0.001). Cardia intestinal metaplasia is associated with H. pylori-related cardia inflammation (P = 0.01) and intestinal metaplasia elsewhere in the stomach, indicating that it is distinct from Barretts esophagus.

Cytomegalovirus Infection and HIV-1 Disease Progression in Infants Born to HIV-1–Infected Women

Background and Methods Cytomegalovirus (CMV) has been implicated as a cofactor in the progression of human immunodeficiency virus type 1 (HIV-1) disease. We assessed 440 infants (75 of whom were HIV-1–infected and 365 of whom were not) whose CMV status was known, who were born to HIV-1–infected women, and who were followed prospectively. HIV-1 disease progression was defined as the presence of class C symptoms (according to the criteria of the Centers for Disease Control and Prevention [CDC]) or CD4 counts of less than 750 cells per cubic millimeter by 1 year of age and less than 500 cells per cubic millimeter by 18 months of age.

The prevalence of coronary artery disease in liver transplant candidates over age 50

The prevalence of angiographically proven coronary artery disease (CAD) in adults with end-stage liver disease who undergo evaluation for liver transplantation is unknown; also it is unclear if cholestatic liver disease represents an independent risk factor. Patients with end-stage liver disease over age 50 having liver transplantation were studied using coronary angiography. Arterial stenosis was graded as normal, mild (< 30%), moderate (30 to 70%), or severe (> 70%). Risk factors for CAD were also assessed (male sex, smoking, hypertension, diabetes, family history of premature heart disease). Complications related to the angiography and decision making based on the findings were recorded. Thirty seven patients (23 females) with a median age of 61 years (range 50 to 71) underwent angiography. Thirteen patients (35.1%) had cholestatic liver disease. Thirty patients had no history of heart disease. The overall prevalence of severe coronary artery disease was 16.2% (95% confidence interval [CI] = 6.2% to 32.0%). No association was detected between CAD and cholestatic liver disease (P = 0.72). After eliminating seven patients with a prior history of angina (n = 1), myocardial infarction (n = 1), or coronary revascularization (n = 5), the frequency of moderate or severe CAD was 13.3% (95% CI = 3.8% to 30.7%). No association was detected between unsuspected CAD and cholestatic liver disease (P = 0.61). Diabetes was the most important risk factor for moderate or severe disease (P = 0.01). Patients without risk factors had significantly less CAD than the group as a whole regardless of the liver disease type (P = 0.02). Two patients experienced transient renal insufficiency after the angiography. Three patients with severe CAD were denied transplantation. We conclude that CAD represents a significant problem in patients over age 50 undergoing liver transplant evaluation. Cholestatic liver disease was not associated with a significantly higher prevalence of moderate or severe CAD in our population. Diabetes was the most predictive risk factor, and those without risk factors do not require extensive preoperative cardiac evaluation.

Spine Fusion Using Cell Matrix Composites Enriched in Bone Marrow-Derived Cells

Bone marrow-derived cells including osteoblastic progenitors can be concentrated rapidly from bone marrow aspirates using the surface of selected implantable matrices for selective cell attachment. Concentration of cells in this way to produce an enriched cellular composite graft improves graft efficacy. The current study was designed to test the hypothesis that the biologic milieu of a bone marrow clot will significantly improve the efficacy of such a graft. An established posterior spinal fusion model and cancellous bone matrix was used to compare an enriched cellular composite bone graft alone, bone matrix plus bone marrow clot, and an enriched bone matrix composite graft plus bone marrow clot. Union score, quantitative computed tomography, and mechanical testing were used to define outcome. The union score for the enriched bone matrix plus bone marrow clot composite was superior to the enriched bone matrix alone and the bone matrix plus bone marrow clot. The enriched bone matrix plus bone marrow clot composite also was superior to the enriched bone matrix alone in fusion volume and in fusion area. These data confirm that the addition of a bone marrow clot to an enriched cell-matrix composite graft results in significant improvement in graft performance. Enriched composite grafts prepared using this strategy provide a rapid, simple, safe, and inexpensive method for intraoperative concentration and delivery of bone marrow-derived cells and connective tissue progenitors that may improve the outcome of bone grafting.