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Direct expenditures related to otitis media diagnoses: extrapolations from a pediatric medicaid cohort.

BACKGROUND: Treatment of otitis media in children is associated with substantial expenditures because of its high frequency during childhood. Vaccines against respiratory pathogens causing otitis media are now being developed. Information about otitis media-related medical expenditures will be needed to determine the cost-effectiveness of these preventive interventions. METHODS: This study used utilization data from claims to impute otitis media-related expenditures for medical visits, pharmaceuticals, and surgical procedures for 87 057 children 13 years of age and younger who were continuously enrolled in Colorado's fee-for-service Medicaid program during 1992. International Classification of Disease, Ninth Revision diagnostic codes were used to identify visits for otitis media. An antibiotic was considered to have been prescribed to treat otitis media if it was dispensed up to 24 hours before or within 48 hours after a physician encounter showing a diagnosis of otitis media. All tympanostomies, mastoidectomies, and adenoidectomies were assumed to be related to otitis media. Expenditures were imputed from utilization using a Medicaid fee schedule. National expenditures for 1992 to treat otitis media were extrapolated from Colorado's Medicaid data. We adjusted for differences between Colorado and the United States as a whole in terms of price, number, and intensity of services; for differences in reimbursement rates by service between Medicaid and private insurance; and for differences in utilization between Medicaid enrollees and the uninsured. To provide a more current expression of medical expenditures for otitis media, we inflated the 1992 expenditure estimates to 1998 dollars using the Consumer Price Index published by the US Bureau of Labor Statistics. RESULTS: Twenty-eight percent of children experienced at least 1 episode of diagnosed otitis media. The proportion of children with a diagnosis of otitis media was highest (42%-60%) in the 7-month to 36-month age range. The proportion was also higher among white (34.5%) and Hispanic (25.3%) children than among black children (18.5%), as well as among rural (34.5%) compared with urban children (27.2%). Children 19 to 24 months of age incurred the highest total annual expenditures per child with otitis media ($239.68). Expenditures for drugs, visits, and procedures were all highest for this group. The per-patient cost to Medicaid was greater for visits than for drugs or procedures across all age groups. Total per-patient expenditures were higher for males ($174.67) than for females ($154.47) and higher for white children ($176.59) than for Hispanic ($154.12) or black children ($134.44). The differences among the ethnic groups can be attributed almost entirely to differences in expenditures for procedures and drugs. Although mean expenditures per patient varied substantially by some patient characteristics (eg, race), these differences accounted for only a small fraction of the enormous variation in costs per patient. Including children with and without otitis media, age-specific estimated expenditures per child peaked among children 1 ($132.94) and 2 years of age ($88.72). Children 3 to 6 years of age incurred expenditures only one third as great as those incurred by children 1 year of age. Total national expenditures were estimated to have been approximately $4.1 billion in 1992 dollars and $5.3 billion in 1998 dollars. Over 40% of national expenditures to treat otitis media in children younger than 14 years of age were incurred for children between 1 and 3 years of age ($453 per capita in 1992 dollars over these 2 years vs $1027 for all years of age from 2 to 13). Nationally, expenditures for visits remained the largest component of expenditures. LIMITATIONS: This study assessed expenditures from the point of view of the health care system; that is, no social costs, such as lost work time, or expenditures not normally covered by insurance, such as those for transportation, we

Adolescent↗

Myxozoan genera: definition and notes on taxonomy, life-cycle terminology and pathogenic species.

A list of myxozoan genera is presented in the current taxonomical scheme. These genera are defined; their type species and most important pathogens along with their hosts are listed. Simultaneously, definitions of actinospore stages representing sexual stages of the myxosporean life cycle are given; altogether, 17 actinospore collective groups with 180 types have been described. Life cycles of the two classes of the phylum Myxozoa, Malacosporea and Myxosporea, are briefly outlined with specification of the appropriate terms. Up to now, 4 malacosporean and 2,180 myxosporean species assigned to a total of 62 genera, have been established. The surviving classification of myxosporeans, based on spore morphology, is discussed in the context of the still fragmentary data resulting from SSU rDNA sequence analyses. The main task for the future is a rigorous, detailed morphological description combined with molecular techniques in establishment of new species and in revision of the existing ones. Establishment of a classification acceptable from morphological, biological and phylogenetical viewpoints is necessary.

Animals↗

[Cryoglobulinemia].

Cryoglobulinaemias contain seric immunoglobulins which precipitate at low temperatures in some tissues. Based on immunohistochemical analysis of their components (monoclonal or polyclonal), 3 types of cryoglobulinaemias have been identified, and a classification has been proposed. The presence of a paraprotein within the cryoglobulinaemia is due to the proliferation of B cells. Type I is mainly associated with a lymphoproliferative syndrome (myeloma and others...) whereas type II (mixed cryoglobulinaemia) and type III are the result of viral and bacterial infectious diseases, and of autoimmune diseases. Over the last few years, infection by hepatitis C has been found in more than 90% of types II and III cryoglobulinaemias. Cryoprecipitates are pathogenic for kidneys, skin and nervous tissues. In some organs, they are responsible for specific histological lesions, such as necrotizing angeitis with vascular microthrombosis. In kidneys, they occur as endocapillary proliferative glomerulonephrites, accompanied by precipitation of immunoglobulins in the form of intracapillary thrombi. Precipitated immunoglobulins can be identified on frozen specimens. Ultrastructural studies confirm the fibrillar aspect which is characteristic of the cryoprecipitate.

Cryoglobulinemia↗

[Adverse cutaneous reactions to drugs in neurology].

Skin drug reactions are cutaneous rashes caused by drugs, through different pathogenic mechanisms that can be classified into two groups: immunologically mediated and non-immunologically mediated. In the first part of this chapter we are going to study the cutaneous reactions to aromatic antiepileptic drugs, namely phenytoin, and focusing attention towards potentially life-threatening drug reactions of an immune cause such as toxic epidermal necrolysis and hypersensitivity syndrome. Secondly we are going briefly summarize skin reactions to drugs usually dealt with in neurological diseases, following a classification based on the morphological aspects of the lesions present in each reaction.

Anticonvulsants↗

Community-acquired and nosocomial pneumonia.

Pneumonia is one of the leading causes of morbidity, hospitalization, and mortality in both industrialized and developing countries. In particular, pulmonary infections acquired in the community, and pneumonias arising in the hospital setting, represent a major medical and economic problem and thus a continuous challenge to health care. For the radiologist, it is important to understand that community-acquired pneumonia (CAP) and nosocomial pneumonia (NP) share a number of characteristics, but should, in many respects be regarded as separate entities. CAP and NP arise in different populations, host different spectra of causative pathogens, and pose different challenges to both the clinician and the radiologist. CAP is generally seen in outpatients, is most frequently caused by Streptococcus pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, and Chlamydia, and its radiologic diagnosis is relatively straightforward. NP, in contrast, develops in the hospital setting, is commonly caused by gram-negative bacteria, and may generate substantial problems for the radiologist. Overall, both for CAP and NP, imaging is an integral component of the diagnosis, important for classification and differential diagnosis, and helpful for follow-up.

Community-Acquired Infections↗

Microreview: capsule-associated genes of Cryptococcus neoformans.

Cryptococcosis, caused by Cryptococcus neoformans is a common systemic mycosis in man and animals, particularly immunocompromised patients. This pathogenic fungus produces a thick extracellular polysaccharide capsule. Four capsule-associated genes (CAP10, CAP59, CAP60, CAP64) were cloned and sequenced, and proved to be essential for capsule synthesis. However biochemical functions of CAP gene products have not been clarified yet. Recently, the relatedness of the polysaccharide capsule and four capsule-associated genes has partly been elucidated. Nucleotide sequence of four CAP gene fragments was analyzed for phylogenetic relationships, and they were in agreement with the conventional classification of varieties and serotypes within C. neoformans. Expression of four CAP genes and capsule size were examined using two media containing different amount of glucose, and the results indicated that CAP genes might play important roles in elaboration of extracellular polysaccharide capsule. Furthermore, analyses of CAP genes in various clinical samples would give the useful information to diagnose cryptococcosis in human and animals.

Animals↗

A quantitative method for assessing the sensitizing potency of low molecular weight chemicals using a local lymph node assay: employment of a regression method that includes determination of the uncertainty margins.

Risk assessment of sensitizing chemicals requires, besides hazard identification, the assessment of potency. To examine the sensitizing capacity of low molecular weight chemicals, a murine local lymph node assay (LLNA) was used. The sensitizing capacity of known allergens was quantified by dose-response modeling. At a stimulatory index (SI) of 3, the corresponding estimated concentration was calculated (EC(3)), together with a confidence interval to take account of the quality of the particular data set. We tested ten allergens (ethyl-p-aminobenzoate (benzocaine), diethylamine (DEA), 2,4-dinitrochlorobenzene (DNCB), 2-mercaptobenzothiazole (MBT), 4-ethoxymethylene 2-phenyl oxazol-5-one (oxazolone), phthalic anhydride (PA), toluene diisocyanate (TDI), trimellitic anhydride (TMA), tetramethylthiuramdisulfide (TMTD) and zincdimethyldithiocarbamate (ZDMC)). Oxazolone showed the strongest sensitizing potency followed in this order by DNCB, TDI, TMA, PA, TMTD, ZDMC, MBT, benzocaine and DEA. The approach performed in this study is a way to accurately assess the potency of sensitizing chemicals and thus a possibility for classification.

Allergens↗

[Pancreatic pseudocysts--possibilities in surgical therapy].

Based on the classification of pseudocysts according to D'Egidio and Schein the different surgical techniques for the treatment of pancreatic pseudocysts, i.e. drainage procedures and resections are discussed. The role of laparoscopic techniques is demonstrated. The "competing" endoscopic and interventional techniques are mentioned. The prognosis of the patients after operations for pancreatic pseudocysts is to a smaller degree depending on the operating technique, but largely on the natural history of the disease and the discontinuation or continuation of the underlying pathogen.

Drainage↗

Sternal surgical-site infection following coronary artery bypass graft: prevalence, microbiology, and complications during a 42-month period.

OBJECTIVE: Surgical-site infection (SSI) is a serious and costly complication following coronary artery bypass graft (CABG). We analyzed surgical factors, microbiology, and complications at a 608-bed community teaching hospital to identify opportunities for prevention. METHODS: All patients undergoing CABG procedures from June 1997 through December 2000 were analyzed. Hospital records and postdischarge surveillance data were reviewed for demographics, surgical information, timing and classification of infection, microbiology, and bacteremic events. RESULTS: Of 3,443 patients undergoing CABG, sternal SSI developed in 122 (3.5%); 71 (58.2%) were classified as superficial SSI and 51 (41.8%) as deep SSI. Surgical antimicrobial prophylaxis was employed in all cases. On average, infection occurred 21.5 days (range, 4 to 315) after CABG. Most cases were diagnosed on readmission (59%); 20 cases (16%) were identified by postdischarge surveillance. Microbiological data were positive in 109 (89.3%), with a single pathogen implicated in most (86.2%). Gram-positive cocci were most frequently recovered (81%); gram-negative bacilli (17%), gram-positive bacilli (1%), and yeast (1%) were less common. Staphylococcus aureus was the most frequently isolated pathogen (49%). Bacteremia was noted in 22 instances (18%). It was significantly associated with deep SSI (P =. 002) and identified only in S. aureus cases. CONCLUSIONS: SSI complicated 3.5% of the procedures. S. aureus was implicated in most of the cases and was significantly associated with deep SSI. It was the only pathogen associated with secondary bacteremia. In addition to standard guidelines, targeted methods against S. aureus should help reduce the overall rate of SSI.

Aged↗

Plasma lactoferrin levels are decreased in end-stage AIDS patients.

The antimicrobial protein lactoferrin (Lf) is present in plasma and in mucosal secretions. Using ELISA we analysed plasma and saliva of HIV-infected patients, patients with AIDS, and healthy controls for the presence of secreted Lf. The plasma Lf levels of AIDS patients (classification C3) were significantly lower (p < 0.001) as compared to asymptomatic and symptomatic HIV infected patients, or controls. In addition, plasma Lf levels closely correlated with neutrophilic granulocyte counts in the HIV-infected patients. Thus, basal plasma Lf levels are likely the result of Lf release by neutrophilic granulocytes. The Candida titres present in the oral cavity were determined in a part of the HIV-infected patient group. As it appeared, the presence of this opportunistic pathogen always coincided with low levels of salivary Lf levels. We conclude that Lf, as part of the nonspecific immune system, might play an important role in the first line of defense against opportunistic microbial infections in AIDS patients.

AIDS-Related Opportunistic Infections↗

[Role of various virus genotypes in progression of chronic hepatitis C].

The relation between HCV genotypes and the progression of chronic hepatitis is still unknown. Some studies implied more pathogenic effect of genotype 1b for the severity of liver inflammation. However, other studies did not show the association between HCV genotype 1b and the severe outcome of HCV infection. The aim of this study was to determine the most frequent genotypes in this environment and their influence on hepatitis C severity. The investigation included 34 patients with histologically confirmed chronic hepatitis C, aged 20-65 (mean 35.0 years). On the basis of pathohistological findings, applying the modern classification, the disease activity was graded as: minimal (A1) moderate (A2) and severe (A3). The extent of fibrosis was marked as: absent (F0), mild (F1), moderate (F2) and severe (F3). Genotyping was performed by nested PCR with type-specific primers and LIPA test and verified by sequencing. The most prevailing genotype in our group of patients was 1b (44.1%), followed by genotype 3a (26.4%), genotype 1a (11.7%) and 2a (2.8%). Five patients had mixed genotypes (four 3a/1b, and one 1a/1b). The severity of liver cell necrosis, measured by alanintransferase (ALT) levels in serum was not related to any of HCV genotypes. There was no statistically significant difference between histological disease activity in relation to HCV genotypes. Stage of the disease was not significantly related to the HCV genotypes. There was a strong association between the degree of fibrosis and the age of patients (p < 0.01). These results could indicate that the determination of HCV genotypes was not useful in the estimation of disease severity and that liver biopsy was the most important for the prognosis of the disease.

Adult↗

The prevalence and etiology of impotence in 101 male hypertensive outpatients.

Erectile dysfunction and impotence has a high prevalence among male hypertensive patients. Whether this relates mainly to specific drug side effects or to primary pathogenic disorders is unknown. In the present study 101 male patients from our outpatient hypertension clinic answered detailed questionnaires about hypertension and sexual function. Patients with perceived impotence were offered a thorough penile evaluation and examination performed by specialists in the urology department. Twenty-seven (27%) men had impotence. The main cause of impotence was an arterial dysfunction (89%). The prevalence of impotence was related to the degree of secondary organ manifestation, reflected by World Health Organization (WHO) classification I-III (P = .01). Intermittent claudication (P = .001) and ischemic heart disease (P = .005) were the best determinants in this respect. Twelve impotent patients (44%) ascribed onset of impotence to drug initiation. A variety of drugs were incriminated in the occurrence of drug-induced impotence. In summary our results indicate that impotence in hypertensive men is caused mainly by penile arterial vascular changes, probably atherosclerosis. Drug-induced impotence could well be the result of blood pressure reduction itself and not specific drug side effects.

Adult↗

Multiple gene genealogies reveal recent dispersion and hybridization in the human pathogenic fungus Cryptococcus neoformans.

Cryptococcus neoformans (= Filobasidiella neoformans) is a significant emerging fungal pathogen of humans. To understand the evolution of this pathogen, 34 strains were obtained from various locations around the world and fragments of four genes were sequenced from each. These strains represented all three varieties and five serotypes. The four sequenced genes are: (i) the mitochondrial large ribosomal subunit RNA; (ii) the internal transcribed spacer region of the nuclear rRNA, including ITS1, 5.8S rRNA subunit and ITS2; (iii) orotidine monophosphate pyrophosphorylase; and (iv) diphenol oxidase. Phylogenetic analyses indicated considerable divergence among lineages, which corresponded to the current classification of C. neoformans into three varieties. However, there is no apparent phylogeographic pattern. Significant incongruences were observed among gene genealogies. The analyses indicated that the major lineages in C. neoformans diverged tens of millions of years ago but have undergone recent dispersion and hybridization.

Catechol Oxidase↗

Haemolysin-deficient variants of Streptococcus pyogenes and S. dysgalactiae subsp. equisimilis may be overlooked as aetiological agents of pharyngitis.

Variants of large colony beta-haemolytic Lancefield group A, C and G streptococci that are non-haemolytic or alpha-haemolytic on sheep blood agar have been detected in clinical specimens due to their enhanced haemolytic activity when grown on a new selective and differential blood agar medium containing colistin, nalidixic acid and pH 7.5-adjusted PIPES buffer (CNA-P). The large colony Lancefield group C and G isolates were identified as Streptococcus dysgalactiae subsp. equisimilis by API 20 Strep classification and 16S rDNA profiling. The haemolytic activity of these variants on various blood agar media, including CNA-P, was closely similar to that of known streptolysin S-defective mutants of S. pyogenes and was blocked by addition of cholesterol, a specific inhibitor of the streptolysin O family of haemolysins. As haemolysin variants could be detected in large numbers in cultures from patients with clinical symptoms of pharyngitis it is suggested that they may function as primary pathogens in such infections. The high frequency with which haemolysin variants were isolated from clinical specimens during a 3-month trial (3%, 13% and 10%, respectively, of group A, C and G streptococcal isolates) indicated that a substantial proportion of streptococcal infections may go undetected if only conventional sheep blood agar media are used in clinical laboratories for the detection of beta-haemolytic streptococci. As haemolysin variants have been implicated in the development of serious streptococcal sequelae, further investigation of the full extent of their contribution to streptococcal disease is indicated.

Antigens, Bacterial↗

[Identification of bacteria through 16S rRNA sequencing: principles, methods and applications in clinical microbiology].

Phylogenetic relationships among prokaryotes can be inferred from comparisons of their 16S rRNA (or 16S rDNA) sequences. This has had an enormous repercussion on bacterial taxonomy, leading to the currently applied system of classification, and allowing a rapid and precise identification of bacteria. In clinical microbiology, molecular identification based on 16S rDNA sequencing is applied fundamentally to bacteria whose identification by means of other types of techniques turns out impossible, difficult, or requires a lot of time. Amplification of the gene to be sequenced uses preferably DNA extracted from a bacterial pure culture, but can be achieved also directly from a clinical sample. The latter has led to the discovery of new pathogens. Bearing in mind its potential, as the technical resources improve and the prize becomes more competitive, the identification based on 16S rDNA sequencing will certainly find a wider application in the clinical microbiology laboratory.

DNA Primers↗

Current concepts in clinical therapeutics: drug therapy in acute renal failure.

The etiology and classification, pathophysiology, diagnosis, clinical course, and drug therapy of acute renal failure (ARF) are reviewed. ARF, a rapid reduction in kidney function that results in decreased glomerular filtration rate and tubular function, is caused by many different factors and can cause multiple organ dysfunction. The major causes of ARF are classically divided into three broad categories: (1) prerenal, or hypoperfusion states, (2) intrarenal, or intrinsic renal parenchymal disease, and (3) post-renal, or urinary obstructive disorders. The underlying pathogenic abnormality is renal tubular cell damage in patients with prerenal azotemia; vascular and glomerular damage is often secondary to immunologic mechanisms. Interstitial nephritis, often drug-induced, results from an immunologically mediated inflammatory renal response. Obstructive nephropathy results from partial or complete blockade of urine flow. Diagnosis relies heavily on patient history and physical examination; laboratory data, renal imaging, and sometimes renal biopsy results can yield important clues. The clinical course of ARF consists of four phases: insult and onset, maintenance, diuresis, and recovery. Morbidity and mortality are high. Drug therapy is directed at preventing or reversing the renal lesion before ARF becomes established and supporting the patient to allow the body to correct the lesion once it occurs. Prevention of prerenal azotemia and intrarenal disease is directed at identifying patients at risk, minimizing nephrotoxicity, and maintaining adequate urine output. In patients with established renal failure, an appropriate intravascular volume and pressure must be re-established and underlying problems must be corrected. Fluid, electrolyte, and acid-base balance are critical, and other serious effects on the gastrointestinal and neurologic systems must be addressed. Even though morbidity and mortality remain unacceptably high in patients with acute renal failure, promising progress has been made during the last 20-30 years.

Acute Kidney Injury↗

[Immune hemolytic anemias (autoimmune, drug-induced)].

The serological investigation of immunohaemolytic anaemias is based on the direct antiglobulin test, on the study of the serum and on the eluate, thus allowing a classification, which is still valid and correlates well with the clinical features. The use of more sensitive techniques and of reagents made from monoclonal antibodies should improve the study of these anaemias, but emphasizes the issue of the limits between physiological and pathological states. The addition of new therapeutical approaches should improve their prognosis. The increasing consumption of drugs and the development of the investigations of the adverse reactions including the haemolytic anaemias have allowed the emergence of new pathogenic concepts. The severity of the course of some of these immune haemolytic anaemia stresses the importance of an adequate therapeutic survey and the development of new means of diagnostic. The clinicians should be aware of the possibility of cross reactivity for drug dependent antibodies with other components of related chimical structure.

Anemia, Hemolytic↗

[Pathology of aortic dissection].

Aortic dissection is not a popular disease but it should be listed in the disease to be excluded especially in acute emergent cases, because of its serious and protean clinical manifestations. While DeBakey classification was used over 30 years. Stanford classification is now widely accepted for its clinical availabilities. The features of the aortic dissection are 1) presence of the intimal tear at the proximal end in almost all cases, 2) its frequent location in the ascending aorta and aortic segment just distal to the left subclavian artery, and 3) the dissected plane at the outer media or medial-adventitial border. Systemic hypertension is frequently noticed in cases with aortic dissection. These features suggest hemodynamic effect as a pathogenic factor in addition to mural fragility of the aorta. Aortic dissection is frequently encountered in Marfan syndrome and other heritable diseases of connective tissue. Concerning Marfan syndrome, mutation of fibrillin gene was confirmed. Fibrillin is a microfibril consisting of glycoprotein closely bound to elastin. Therefore, traditional "cystic medial necrosis" which was referred as a principal morphological change corresponding to aortic dissection is now thought to be a secondary change to the aortic injuries occurred in the aortic wall.

Aortic Dissection↗