Virgil F. Fairbanks

Incidence of Anemia in Older People: An Epidemiologic Study in a Well Defined Population

OBJECTIVE: To assess the incidence and clinical spectrum of anemia among older people.

Screening for hemochromatosis: A cost-effectiveness study based on 12,258 patients

BACKGROUND/AIMS Current emphasis in hemochromatosis has focused on early detection and treatment to prevent permanent liver damage and hepatocellular carcinoma. Thus far, only normal population and high-risk groups have been screened but not patients seeking medical care. METHODS Serum iron levels were determined in consecutive fasting blood samples collected in the morning from 12,258 Mayo Clinic patients. RESULTS One hundred twenty-seven patients had an initial serum iron concentration > or = 180 micrograms/dL. Eight patients (age, 38-71 years; 7 men and 1 woman) had transferrin saturation > or = 62% (range, 84-99) and serum ferritin value > or = 400 micrograms/L (range, 457-4004) with no other explanation for the abnormal iron test results. Three patients (2 male and 1 female) had markedly elevated hepatic iron concentration (range, 11,080-29,719 micrograms/g dry wt) and hepatic iron index (range, 2.9-8.4) indicative of homozygous hemochromatosis. One patient who refused liver biopsy had 7 g of iron removed by phlebotomy and is likely homozygous. Two patients had hepatic iron indices < 1.5 and are probably heterozygous. The genetic status of 1 patient is indeterminate, and 1 patient with normal hepatic iron concentration and hepatic iron index had chronic active hepatitis. None had cirrhosis, diabetes, or cardiomyopathy. No patients with hemochromatosis would have been detected without this study. CONCLUSIONS The yield in this study, 0.33 cases of 1000 screened, is approximately one tenth of the predicted homozygote frequency by recent estimates. Even at this yield, screening appears cost-effective.

Prevalence of Anemia in Medical Practice: Community Versus Referral Patients

OBJECTIVE To compare the prevalence of anemia among community and referral patients. DESIGN A Mayo Clinic laboratory database was searched for hemoglobin determinations between Jan. 1, 1985, and Dec. 31, 1989, in residents and nonresidents of Olmsted County, Minnesota, who were 20 years of age or older (a more restricted period within this interval was used for those 70 years of age or older). MATERIAL AND METHODS Using the World Health Organization criteria for anemia, we estimated the prevalence of anemia as of July 1, 1987, among Olmsted County residents 20 years of age or older (community patients) and compared this finding with the prevalence among non-Olmsted County patients of the same age registered at the Mayo Clinic during the same year (referral patients). RESULTS The crude prevalence of anemia among Olmsted County men was less than that among male referral patients, but this difference was decreased by adjusting for the older mean age of referral patients (6.6% versus 7.0%; P = 0.01). Even after age-adjustment, the prevalence of anemia was greater among community women than among female referral patients (12.4% versus 8.2%; P < 0.001). Before age 55 years, the prevalence of anemia was lower among men than among women, but after that age, anemia became more frequent in men, reaching a 44.4% prevalence among community men 85 years of age or older. The overall prevalence rate was sensitive to the criteria used to define a low hemoglobin level, however. CONCLUSION Clinicians should be aware of the high prevalence of anemia, especially among elderly community patients. This precaution should help minimize the overlooked diagnosis of anemia and the failure to identify and treat its underlying cause.

Hemoccult detection of fecal occult blood quantitated by radioassay

Results from the guaiac slide or Hemoccult (HO) test for fecal occult blood were compared with quantitative determinations of gastrointestinal loss after intravenous administration of51Cr-labeled red cells. Subjects were 80 consecutive patients, without dietary restriction, who were referred because of clinical suspicion of gastrointestinal blood loss or complex anemia. A total of 555 stool specimens analyzed for51Cr loss were graded negative, trace, or positive by the HO method. Of 338 specimens containing 0–2 ml/day by isotope assay, 7.4% were positive to the HO qualitative test. Loss of at least 10 ml/day in51Cr equivalent was necessary to assure that the majority of HO reactions would be positive. Of specimens containing more than 30 ml/day, 93% were positive. The ratio of51Cr-labeled red cell equivalents to stool volume and the percentage of positive HO reactions increased together. When this ratio exceeded 10%, two thirds of the HO responses were positive.

Liver Biopsy Diagnosis of Homozygous Hemochromatosis: A Diagnostic Algorithm

The diagnosis of homozygous hemochromatosis (HH) should be based on appropriate findings on liver biopsy specimens. In cases with equivocal morphologic features, quantitative tissue iron determination and calculation of the hepatic iron index generally enable one to distinguish HH from other types of hepatic iron overload. In this article, we describe a diagnostic algorithm that is designed to avoid diagnostic errors because of histologic misinterpretation or erroneous, usually false-negative, chemical iron studies. The algorithm also delineates a cost-effective method of using quantitative tissue iron analysis. Diagnostic biopsy features of uncomplicated HH include (1) hemosiderosis that involves primarily hepatocytes, with or without inactive cirrhosis, and (2) a tissue iron index of 1.9 or higher. Findings such as prominent fatty changes or lymphocytic piecemeal necrosis indicate the presence of HH in conjunction with another complicating condition or secondary iron overload in the absence of HH.

Normal ranges for packed cell volume and hemoglobin concentration in adults: relevance to ‘apparent polycythemia’

Abstract: Published data from Europe and North America indicate that for non‐iron‐deficient adult Caucasian males, the normal mean packed cell volume (PCV) is 0.46 and the 2.5–97.5 percentile interval is04.0–0.53. Corresponding values for adult Caucasian females are: mean PCV 0.42; 2.5–97.5 percentile interval 0.36–0.48. It is not usually appropriate to undertake studies of polycythemia in adult Caucasian males with PCV<0.55 (Hb Conc.<180 g/L) or in adult Caucasian females with PCV<0.50 (Hb Conc. <16.5 g/L). Application of this principle will reduce the number of inappropriate and costly studies that would otherwise be performed in patients whose PCV values are only in the upper percentiles of the normal range, and will help to avoid misdiagnoses and therapeutic misadventures.

Red cell mass and plasma volume measurements in polycythemia: evaluation of performance and practical utility.

Despite the absence of any systematic evidence for diagnostic utility, red cell mass (RCM) measurement has been endorsed as a major diagnostic criterion for polycythemia vera (PV) based on a set of eligibility criteria for a clinical trial formulated by an International PV Study Group in 1967.

Methemoglobinemia From Topically Applied Anesthetic Spray

Topically applied anesthetic spray is commonly used as part of premedication for general anesthesia and for endoscopic procedures; it is rarely associated with side effects. In this report, we describe two cases of toxic methemoglobinemia that resulted from topically applied anesthetic spray used before endoscopy. In both cases, standard doses were used; however, methemoglobin levels of 45% and 38% developed within 1 hour of the procedure. Both patients had normal levels of erythrocyte methemoglobin reductase, an indication that this rare but potentially fatal side effect can occur in persons who have no predisposing factors. Because toxic methemoglobinemia is easily treated, our report emphasizes the need to recognize this problem when topically applied anesthetic sprays are used.

Prevalence and clinical significance of HFE gene mutations in patients with iron overload

Prevalence and clinical significance of HFE gene mutations in patients with iron overload

Flow Cytometric Measurement of Hemoglobin F in RBCs Diagnostic Usefulness in the Distinction of Hereditary Persistence of Fetal Hemoglobin (HPFH) and Hemoglobin S-HPFH From Other Conditions With Elevated Levels of Hemoglobin F

The cellular distribution of hemoglobin F is important for evaluating persistently elevated hemoglobin F levels, such as in hereditary persistence of fetal hemoglobin (HPFH) or delta/beta-thalassemia, and for differentiating homozygous hemoglobin S (or hemoglobin S-beta(0)-thalassemia) from hemoglobin S-HPFH, traditionally done by using the Kleihauer-Betke (K-B) acid elution test. We evaluated a flow cytometric method using an anti-hemoglobin F antibody as a replacement for the K-B test. We used 172 specimens representing a variety of conditions: HPFH trait, 19 cases; delta/beta-thalassemia trait, 8 cases; hemoglobin S-HPFH, 10 cases. By flow cytometry, all cases of HPFH trait gave a hemoglobin F pattern comparable to the homocellular pattern obtained by the K-B test; all cases of delta/beta-thalassemia tested gave a pattern comparable to a K-B heterocellular pattern. Most cases of hemoglobin S-HPFH gave a homocellular distribution of hemoglobin F whereas all cases of homozygous hemoglobin S with elevated hemoglobin F levels gave a heterocellular pattern. Flow cytometry provides a more rapid and objective method for assessing cellular distribution of hemoglobin F and is useful for patient evaluation when HPFH trait, delta/beta-thalassemia trait, or hemoglobin S-HPFH trait is suspected.