Antimitochondrial antibodies of primary biliary cirrhosis recognize dihydrolipoamide acyltransferase and inhibit enzyme function of the branched chain alpha-ketoacid dehydrogenase complex

Antimitochondrial antibodies (AMA) recognizing the acetyltransferase (E2) of the pyruvate dehydrogenase (PDH) complex have been previously well-documented and the immunodominant epitope mapped. In this study, we demonstrate that sera from patients with primary biliary cirrhosis (PBC) react with another lipoic acid containing acyltransferase enzyme, namely the E2 of the branched chain alpha-ketoacid dehydrogenase (BCKD) complex. Indeed, 85/120 (71%) sera from patients with PBC reacted with BCKD-E2 by immunoblotting against purified BCKD complex. In contrast, sera from patients with chronic active hepatitis or progressive sclerosing cholangitis as well as sera from healthy volunteers did not react with any component enzymes of the BCKD complex. More importantly, BCKD enzyme activity was inhibited after incubation of the BCKD complex with either PBC sera against BCKD-E2 or with affinity purified antisera to BCKD-E2. Enzyme activity was unaltered by control sera or with PBC sera that reacted with PDH-E2 but not BCKD-E2. Furthermore, immunoblots of purified mitochondria probed with PBC sera absorbed with BCKD-E2 demonstrated that BCKD-E2 and PDH-E2 are each recognized by distinct AMA populations which do not cross-react. In addition, affinity purified PBC sera against BCKD-E2 did not react with PDH-E2 nor inhibit PDH enzyme activity, thus providing further evidence that BCKD-E2 and PDH-E2 are recognized by separate AMA. These data further suggest that the BCKD-E2 epitope recognized by AMA contains, or is close to, a functional domain of this enzyme. The availability of cDNA clones encoding BCKD-E2 and PDH-E2 will allow the study of how key metabolic enzymes may be involved in the immunology and pathology of PBC.

Detection of autoantibodies to recombinant mitochondrial proteins in patients with primary biliary cirrhosis

Primary biliary cirrhosis is characterized by the presence of autoantibodies to mitochondria with specific reactivity to proteins of 74 and 52 kilodaltons (kd). The 74-kd mitochondrial protein is the E2 component--dihydrolipoamide acetyltransferase--of the pyruvate dehydrogenase complex, and the 52-kd protein is the equivalent E2 component--dihydrolipoamide acyltransferase--of the branched-chain alpha-keto acid dehydrogenase complex. Current methods for the detection of antibodies to these proteins lack specificity or sensitivity, or they are time-consuming and not readily available. We therefore developed an enzyme-linked immunoassay to quantify specific antimitochondrial antibodies in patients with primary biliary cirrhosis. Recombinant polypeptides coding for both the 74-kd and the 52-kd mitochondrial autoantigens were used to analyze 217 coded serum samples, including samples from 93 patients with primary biliary cirrhosis and 124 controls, for reactivity by our immunoassay, immunoblotting, and immunofluorescence testing. Serum samples from 89 of the 93 patients with primary biliary cirrhosis reacted with either the pyruvate dehydrogenase-E2 or the branched-chain alpha-keto acid dehydrogenase protein. None of the 124 control samples from healthy volunteers (n = 86) or patients with primary sclerosing cholangitis (n = 38) had significant reactivity. Our results indicate that the use of recombinant, cloned autoantigens provides a simple, accurate, and rapid method of quantifying and monitoring the levels of specific mitochondrial autoantibodies in the serum of patients with primary biliary cirrhosis.

Immunization of experimental animals with dihydrolipoamide acetyltransferase, as a purified recombinant polypeptide, generates mitochondrial antibodies but not primary biliary cirrhosis

The availability of recombinant mitochondrial autoantigens may permit the experimental study of the pathophysiology of primary biliary cirrhosis. Previously, we demonstrated that high-titer antibodies to the 74 kD mitochondrial autoantigen dihydrolipoamide acetyltransferase could be generated when BALB/c mice were immunized with purified recombinant protein. Based on these data, we attempted an 8-month study to induce antibodies and liver dysfunction by immunizing AKR/J, C3H/J and CBA/HeJ mice as well as rats, guinea pigs, rabbits and rhesus monkeys with purified recombinant human dihydrolipoamide acetyltransferase. Antibodies to dihydrolipoamide acetyltransferase were readily induced and detected in all species of experimental animals with species and strain differences in the titer of the responses. Of particular interest, rabbits and guinea pigs produced antibodies which were specifically reactive with the functional site of dihydrolipoamide acetyltransferase, whereas the other strains and species produced antibodies to other epitopes on the molecule. Finally, similar to data on humans with primary biliary cirrhosis, the pyruvate dehydrogenase enzyme pathway was inhibited in the presence of immunized animal sera. These data imply that features other than simply an antibody response to mitochondrial enzymes are required for the development of primary biliary cirrhosis. Further studies will be necessary to determine the mechanisms by which mitochondrial proteins elicit an immune response.

Deep vein versus pseudo deep vein thrombosis: the role of imaging techniques in differential diagnosis and management

An acutely swollen, painful calf is usually caused by deep vein thrombosis or pseudo deep vein thrombosis; however, the differential diagnosis and management of these 2 entities can prove difficult and even hazardous unless a careful, systematic approach is used. This article describes the use of 2 invasive techniques (ascending venography and arthrography) and several noninvasive methods (magnetic resonance imaging, computerized axial tomography, and non-Doppler ultrasound) to differentiate between deep vein thrombosis and pseudo deep vein thrombosis. The author discusses a practical, cost-effective approach to diagnosing and managing the acutely swollen, painful calf.

In vitro functional characterization of SAG-3--a naturally occurring monoclonal antibody in NZB mice: specificity toward functional T cell subsets

Natural thymocytotoxic autoantibodies (NTA) have been suggested to contribute to the T cell mediated immune dysfunction prevalent in NZB mice. However, direct studies to confirm these suggestions have been difficult to perform due to the absence of large amounts of pure NTA. To overcome this problem, we generated a naturally occurring monoclonal antibody from an NZB mouse which possesses the serological characteristics of serum-NTA. Herein, we report the in vitro functional characteristics of this monoclonal antibody designated SAG-3. In vitro treatment of spleen and lymph node cells from BALB/c mice with SAG-3 and complement eliminated most of the proliferative response to Con-A and moderately reduced the response of these cells to PHA-P and PWM. Complement mediated cytolysis of SAG-3 reactive cells significantly reduced the capacity of unprimed lymph node cells to generate primary CTL responses in vitro against allogeneic cells. However, only a partial decrease in CTL activity was observed when primed secondary CTL effector cells were treated, due primarily to the depletion of CTL's specific towards MHC class I antigens. Furthermore, a moderate reduction in antigen-specific helper T cell function was observed. Pretreatment of responder cells with SAG-3 + C' did not appear to reduce the proliferative MLR response to a wide range of stimulator cells. In addition, contrary to previous reports on serum-NTA, SAG-3 appears not to be reactive against Con-A induced suppressor T cells. Finally, by FACS analysis SAG-3+ thymocytes constitute an overlapping population of Lyt-2+ and L3T4+ thymocytes. These findings are discussed in comparison to previous reports on NTA.

Ligand binding to synthetic mutant myoglobin (His-E7----Gly): role of the distal histidine

Low-temperature flash photolysis with IR and visible spectroscopy was used to probe the influence of the distal histidine His-64(E7) of sperm-whale myoglobin (Mb) on the orientation of bound carbon monoxide (CO) and on the kinetics of CO rebinding. The synthesis and high-level expression of a sperm-whale myoglobin gene in Escherichia coli permits the efficient substitution of the distal histidine through site-directed mutagenesis. Substitution of His-E7 with glycine [GlyE7]Mb bound with CO (CO[GlyE7]Mb) results in one broad bound-CO IR stretch band, v(C-O), centered at 1973 cm-1 at 10 K, in contrast to three distinct bands for native and synthetic wild-type MbCO at 1966, 1945, and 1929 cm-1. After flash photolysis at 10 K, the unbound state of CO[GlyE7]Mb exhibits two CO stretch bands, whereas MbCO has three. Fourier transform IR spectroscopy measurements of the linear dichroism after photoselective flash photolysis of CO bound to [GlyE7]Mb at 10 K reveals the bound CO to be oriented at an angle of alpha = 20 degrees +/- 2 degrees with respect to the heme normal. Flash photolysis data from 10 to 300 K provide evidence for a larger distal pocket and a smaller enthalpy barrier (by approximately 4 kJ/mol) for [GlyE7]MbCO as compared with wild-type MbCO. These results reinforce the notion that the dominant control of the binding step at the heme iron comes from the proximal side through the protein structure.

Autoantibodies of primary biliary cirrhosis recognize dihydrolipoamide acetyltransferase and inhibit enzyme function

Autoantibodies against mitochondria occur in the sera of patients with primary biliary cirrhosis (PBC) with characteristic reactivity to an inner membrane protein of approximately 74 kDa. To precisely define these autoantigens, we recently cloned and sequenced a rat liver cDNA (pRMIT) that encodes for all of the epitopes recognized by Ig to the 74-kDa autoantigen. In the present study we have used this recombinant probe as a tool, in addition to purified enzymes, to demonstrate by immunoblotting that the 74-kDa mitochondrial autoantigen is dihydrolipoamide acetyltransferase (EC 2.3.1.12), the core protein of the pyruvate dehydrogenase complex. Furthermore, and of particular interest, inhibition of pyruvate dehydrogenase enzyme activity was demonstrated after incubation with sera from patients with PBC but not from normal volunteers or patients with chronic active hepatitis. Such inhibition was abrogated by absorption of the PBC sera with an expressing subclone of pRMIT, designated pRMIT-603. Identification of dihydrolipoamide acetyltransferase as the target of autoimmunity in PBC provides a reagent that can be used to determine mechanisms by which this molecule is recognized. It will allow study of whether autoimmune reactivity, at the humoral or T cell level, is the basis for the pathogenesis of PBC. Additionally, such data present evidence of functional inhibition of a critical metabolic enzyme. Dihydrolipoamide acetyltransferase is well-known to mitochondrial biochemistry and, similar to identified autoantigens in other autoimmune diseases, is highly conserved in evolution.

Autoantibodies of primary biliary cirrhosis recognize dihydrolipoamide acetyltransferase and inhibit enzyme function

Autoantibodies against mitochondria occur in the sera of patients with primary biliary cirrhosis (PBC) with characteristic reactivity to an inner membrane protein of approximately 74 kDa. To precisely define these autoantigens, we recently cloned and sequenced a rat liver cDNA (pRMIT) that encodes for all of the epitopes recognized by Ig to the 74-kDa autoantigen. In the present study we have used this recombinant probe as a tool, in addition to purified enzymes, to demonstrate by immunoblotting that the 74-kDa mitochondrial autoantigen is dihydrolipoamide acetyltransferase (EC 2.3.1.12), the core protein of the pyruvate dehydrogenase complex. Furthermore, and of particular interest, inhibition of pyruvate dehydrogenase enzyme activity was demonstrated after incubation with sera from patients with PBC but not from normal volunteers or patients with chronic active hepatitis. Such inhibition was abrogated by absorption of the PBC sera with an expressing subclone of pRMIT, designated pRMIT-603. Identification of dihydrolipoamide acetyltransferase as the target of autoimmunity in PBC provides a reagent that can be used to determine mechanisms by which this molecule is recognized. It will allow study of whether autoimmune reactivity, at the humoral or T cell level, is the basis for the pathogenesis of PBC. Additionally, such data present evidence of functional inhibition of a critical metabolic enzyme. Dihydrolipoamide acetyltransferase is well-known to mitochondrial biochemistry and, similar to identified autoantigens in other autoimmune diseases, is highly conserved in evolution.

The autoepitope of the 74-kD mitochondrial autoantigen of primary biliary cirrhosis corresponds to the functional site of dihydrolipoamide acetyltransferase

Autoantibodies to mitochondrial antigens are characteristic of the autoimmune liver disease primary biliary cirrhosis (PBC), but the precise antigenic determinants recognized by these antibodies have not been defined. Recently, our laboratory identified a 1,370-bp rat liver cDNA clone that coded for a polypeptide recognized specifically by sera from patients with PBC but not by sera from patients with other forms of liver disease. This recombinant protein was identified as the 74-kD M2 mitochondrial inner membrane autoantigen, now known to be dihydrolipoamide acetyltransferase. In the present study, we have identified a 603-bp fragment that codes for a polypeptide containing all of the autoreactivity of the original clone. In addition, based on hydrophobicity/hydrophilicity plots of the amino acid sequence of this polypeptide segment, several peptides were synthesized and tested for reactivity by an inhibition assay using sera from patients with PBC. One peptide, defined by the amino acids AEIETDKATIGFEVQEEGYL, absorbed serum reactivity to the protein product of the original clone. Of particular interest was the finding that this peptide contains the lipoic acid binding site KATIGF of the dihydrolipoamide acetyltransferase found in the inner mitochondrial membrane. Thus, it appears that for this autoantigen, the target of the autoantibodies corresponds to a functional site of the dihydrolipoamide acetyltransferase.

Early evening ranitidine administration promotes faster duodenal ulcer healing

In a prospective double-blind clinical trial, 141 patients with endoscopically diagnosed duodenal ulcer were randomly assigned to treatment with ranitidine 300 mg, taken either at 6 PM or at 10 PM. After 2 wk of treatment, 52 of 70 patients (74%) in the 6 PM treatment group had healed, compared with 32 of 64 patients (50%) taking ranitidine at 10 PM (p less than 0.01). After 4 wk, the cumulative healing rates were 100% and 94%, respectively, for the 6 PM and 10 PM treatment regimens. These results suggest that ranitidine, taken as a single daily 300-mg dose at 6 PM after dinner, provides more rapid duodenal ulcer healing than the same dose of the drug taken at 10 PM.

Rebinding and relaxation in the myoglobin pocket

The infrared stretching bands of carboxymyoglobin (MbCO) and the rebinding of CO to Mb after photodissociation have been studied in the temperature range 10-300 K in a variety of solvents. Four stretching bands imply that MbCO can exist in four substates, A0-A3. The temperature dependences of the intensities of the four bands yield the relative binding enthalpies and and entropies. The integrated absorbances and pH dependences of the bands permit identification of the substates with the conformations observed in the X-ray data (Kuriyan et al., J. Mol. Biol. 192 (1986) 133). At low pH, A0 is hydrogen-bonded to His E7. The substates A0-A3 interconvert above about 180 K in a 75% glycerol/water solvent and above 270 K in buffered water. No major interconversion is seen at any temperature if MbCO is embedded in a solid polyvinyl alcohol matrix. The dependence of the transition on solvent characteristics is explained as a slaved glass transition. After photodissociation at low temperature the CO is in the heme pocket B. The resulting CO stretching bands which are identified as B substates are blue-shifted from those of the A substates. At 40 K, rebinding after flash photolysis has been studied in the Soret, the near-infrared, and the integrated A and B substates. All data lie on the same rebinding curve and demonstrate that rebinding is nonexponential in time from at least 100 ns to 100 ks. No evidence for discrete exponentials is found. Flash photolysis with monitoring in the infrared region shows four different pathways within the pocket B to the bound substates Ai. Rebinding in each of the four pathways B----A is nonexponential in time to at least 10 ks and the four pathways have different kinetics below 180 K. From the time and temperature dependence of the rebinding, activation enthalpy distributions g(HBA) and preexponentials ABA are extracted. No pumping from one A substate to another, or one B substate to another, is observed below the transition temperature of about 180 K. If MbCO is exposed to intense white light for 10-10(3) s before being fully photolyzed by a laser flash, the amplitude of the long-lived states increases. The effect is explained in terms of a hierarchy of substates and substate symmetry breaking. The characteristics of the CO stretching bands and of the rebinding processes in the heme pocket depend strongly on the external parameters of solvent, pH and pressure. This sensitivity suggests possible control mechanisms for protein reactions.

Pseudopericardial effusion: echocardiographic and computed tomographic correlations

The findings of small anterior and posterior relatively echo-free spaces adjacent to the epimyocardium by echocardiography is more often indicative of pseudopericardial effusion due to subepicardial fat deposition rather than true pericardial effusion (PE), at least in older obese and Type II diabetic patients. This conclusion was based on the echo and computed tomography (CT) correlation performed in 10 consecutive patients (8 women, 2 men). The mimicry of various extracardiac and cardiac causes resulting in confusion with anterior and posterior PE is emphasized. Subepicardial fat deposition is one of the most common causes which mimic presence of small PE on echo and can be confirmed easily by limited CT of the chest. Age, sex, obesity, and diabetes mellitus (Type II) appear to be the most common predisposing factors for the accumulation of excess subepicardial fat.

Childhood familial pheochromocytoma. Conflicting results of localization techniques

Childhood familial pheochromocytoma was investigated in four patients by abdominal computed tomographic scan, [131I]metaiodobenzylguanidine scan, and vena caval catecholamine sampling. Results conflicted with surgical findings. Computed tomographic scan identified all four adrenal tumors but missed two midline tumors in one patient. [131I]metaiodobenzylguanidine scan identified two of three adrenal tumors but also suggested extra-adrenal tumors not confirmed at operation in two of three patients. Vena caval sampling for catecholamines confirmed all adrenal tumors but suggested additional tumors not verified at operation in two of three patients. All patients are asymptomatic and have normal urinary catecholamines 15 to 51 months after operation. Because of the frequency of multiple tumors in familial pheochromocytoma, different diagnostic techniques were employed. False-positive results were more frequent with [131I]metaiodobenzylguanidine and vena caval sampling. Reinterpretation of the [131I]metaiodobenzylguanidine scans at a later date led to less false-positive interpretation, although the false-negative rate remained unchanged. More pediatric experience with [131I]metaiodobenzylguanidine scans and vena caval sampling in familial pheochromocytoma is needed. Confirmation of tumor and its localization rest with meticulous surgical exploration.

Acute and chronic pulmonary thromboembolism: current perspectives. Part I: Glossary of terms, historic evolution and prevalence

Despite considerable medical as well as surgical advances, the problem of pulmonary thromboembolism, both acute and chronic, continues to plague clinicians of all medical disciplines. Approximately 650,000 to 700,000 patients per year suffer from acute pulmonary thromboembolism in the United States. Of these, approximately 60,000-70,000 die as a direct result of it. Our knowledge of the etiology, pathology, pathogenesis of pulmonary infarction, pathophysiology, accurate diagnosis, proper management (including both primary and secondary prophylaxis) of deep vein thrombi and pulmonary thromboemboli has advanced considerably during the past 15 years. These advances, which have now been adopted in the clinical practice, have already begun to indicate that not only more cases of acute and chronic pulmonary thromboembolism are being recognized than before, but also the morbidity and mortality of this disease process is declining. This is likely to improve further as our quest for safe, accurate, noninvasive and inexpensive diagnostic methods continues. Medical thromboembolectomy using thrombolytic therapy is fast replacing the surgical thromboembolectomy for patients with acute massive pulmonary thromboembolism. Better thrombolytic agents, such as tissue plasminogen activator, which selectively lyses the thromboemboli without producing significant systemic lytic state and now undergoing clinical investigation, is likely to revolutionize the management of both acute and chronic pulmonary thromboembolism because of its propensity to dissolve plasminogen-bound thrombi of any age. The majority of the patients who suffer from acute pulmonary thromboembolism recover most of their lost lung function unless cardiopulmonary reserve was compromised prior to the onset of the acute episode.(ABSTRACT TRUNCATED AT 250 WORDS)

Ligand binding to heme proteins: relevance of low-temperature data

Binding of carbon monoxide to the beta chain of adult human hemoglobin has been studied by flash photolysis over the time range from about 100 ps to seconds and the temperature range from 40 to 300 K. Below about 180 K, binding occurs directly from the pocket (process I) and is nonexponential in time. Above about 180 K, some carbon monoxide molecules escape from the pocket into the protein matrix. Above about 240 K, escape into the solvent becomes measurable. Process I can be observed up to 300 K. The low-temperature data extrapolate smoothly to 300 K, proving that the results obtained below 180 K provide functionally relevant information. The experiments show again that the binding process even at physiological temperatures is regulated by the final binding step at the heme iron and that measurements at high temperatures are not sufficient to fully understand the association process.

Vascular manifestations of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a well-known acute and/or chronic multisystem disease of complex autoimmune nature, having predilection for cardiovascular system. While its cardiac manifestations have been adequately studied, there is paucity of information on its vascular manifestations. Accordingly, we studied the incidence of vascular manifestations in 50 consecutive SLE patients seen at our institutions and in private practice during the past 12 years. Systemic hypertension (44%) was the most common vascular manifestation followed by vasculitis (30%), Raynaud's phenomenon (26%), telangiectasis (20%), premature coronary atherosclerosis (6%), digital ulceration (6%), thrombophlebitis (6%), pulmonary hypertension (4%) and portal hypertension (4%). Diffuse systemic vasculitis similar to polyarteritis nodosa was rare (2%). Often more than one lesion was found in the same patient. The clinical diagnosis of these vascular manifestations in the context of the primary disease (SLE) usually does not pose any difficulty except when they antedate it. We also studied the pathology and pathogenesis of some of these vascular lesions in both autopsy and biopsy specimens by both light microscopy and immunofluorescent techniques. Our results as well as those of others who also studied these lesions indicate that immune complex deposition and subsequent complement activation play an important role in the pathogenesis of vasculitis, coronary arteritis and premature coronary atherosclerosis. Corticosteroids and vasodilators remain the drugs of choice for the management of the majority of the symptoms arising from the vascular lesions of SLE.

M-mode echocardiography in supine and standing position in control subjects and patients with auscultatory evidence of mitral valve prolapse but negative supine echocardiography: does sensitivity improve?

Approximately 10-20% of patients with auscultatory evidence of mitral valve prolapse (MVP) have "false negative" echocardiograms. Pharmacological maneuvers do not significantly improve the sensitivity and may cause side effects. It is well known that auscultatory features of MVP change and not uncommonly can be heard only in the standing position. Therefore M-mode echo was performed in both supine and standing positions in 10 normal control subjects and 25 patients of comparable age and sex who had auscultatory evidence of MVP but negative echo in supine position. All 10 control subjects had normal echo in both supine and standing positions. No instance of false positive MVP was noted. Of the 25 patients with "false negative" supine echo, 5 showed evidence of MVP (3 pansystolic and 2 late systolic) in standing position. Based on these results the following conclusions were reached. In normal individuals the MVE remains uninfluenced by change in posture. There is modest (20%) improvement in sensitivity of detecting MVP when M-mode echo is performed in standing position in addition to supine position. Change in posture is preferable to the use of pharmacological maneuver to improve the sensitivity of detecting MVP because it is physiological, devoid of any cost, and does not produce side effects. M-mode echo in standing position or two-dimensional echo in supine position can be used to confirm the diagnosis of MVP in those patients who have "false negative" and/or nondiagnostic supine echo in the presence of auscultatory features of midsystolic click and mid- or late-systolic murmurs.

Protein states and proteinquakes

After photodissociation of carbon monoxide bound to myoglobin, the protein relaxes to the deoxy equilibrium structure in a quake-like motion. Investigation of the proteinquake and of related intramolecular equilibrium motions shows that states and motions have a hierarchical glass-like structure.

Cardiovascular manifestations of systemic lupus erythematosus: current perspective

Cardiovascular manifestations develop in the majority of SLE patients at some time during the course of their illness, the most common being acute fibrinous pericarditis and pericardial effusion. Echocardiography has demonstrated an increased incidence of pericardial effusion, even in those who have minimal symptoms. Chronic adhesive pericarditis, pericardial tamponade, and constrictive pericarditis occur rarely. While myocarditis is commonly noted at autopsy, it is often silent clinically. Diagnosis during life can be confirmed only by endomyocardial biopsy. Electrocardiographic changes are often nonspecific. Endocarditis with superimposed nonbacterial verrucous vegetations (Libman-Sacks) is noted in more than 40% of hearts at autopsy, but is rarely diagnosed during life. Valve dysfunctions, such as aortic stenosis, aortic insufficiency, mitral stenosis, and mitral insufficiency, occasionally manifest during life and rarely may necessitate surgery. Atrial and ventricular arrhythmias, first degree AV block, and acquired CHB occur in association with pericarditis, myocarditis, vasculitis, and myocardial fibrosis, respectively. CCHB developing in newborns of mothers with SLE, particularly those who have an antibody to soluble tissue ribonuclear protein RO(SS-A), is increasingly being appreciated by both pediatric cardiologists and rheumatologists. Recently, severe coronary atherosclerosis resulting in angina pectoris and/or myocardial infarction in young adults has been noted, particularly in those who had developed risk factors such as hypertension and hyperlipidemia while receiving prolonged corticosteroid therapy. Rarely, coronary arteritis may produce similar symptoms. Congestive heart failure of either single or multiple etiologies carries an ominous prognosis. It remains a cause of high morbidity and mortality unless recognized early and treated properly. Extracardiac vascular manifestations of SLE include telangiectasia, vasculitis, livedo reticularis, Raynaud's phenomena, and thrombophlebitis, all of which may occur either alone or in different combinations. Evidence is now slowly accumulating that substantiates that immune complex deposition, complement activation and subsequent inflammatory reaction is responsible for the majority of the cardiovascular manifestations of SLE, for example, pericarditis, myocarditis, endocarditis, coronary arteritis, coronary atherosclerosis, and systemic and pulmonary vasculitis.(ABSTRACT TRUNCATED AT 400 WORDS)

The "straight back" syndrome: current perspective more often associated with valvular heart disease than pseudoheart disease: a prospective clinical, electrocardiographic, roentgenographic, and echocardiographic study of 50 patients

Fifty consecutive patients (36 male, 14 female, mean age 28 years) who had heart murmurs and clinical and radiographic evidence of straight upper dorsal spine (straight back syndrome, SBS) underwent detailed clinical, electrocardiographic, roentgenographic, and echocardiographic evaluation. Palpable systolic thrill noted in one (2%) and widened S2 with persistent splitting in 2 (4%) patients were uncommon. Murmurs were invariably systolic in nature. Those located at the base of the heart in 19 (38%) patients were ejection in type and best heard during expiration. Those located at the apex in 26 (52%) patients were either mid-, late-, or pansystolic, and often associated with midsystolic click. Five (10%) patients had both types of murmurs. Diastolic murmurs were not heard in any patient. EKGs were normal in the majority. Cardiomegaly (C:T greater than 55%) was present in only 5 (10%) and dilatation of the main pulmonary artery in 2 (4%) patients. Thus the incidence of pseudoheart disease (PsHD) was small (14%). Echocardiograms were normal in 18 (36%) and abnormal in 32 (64%) patients. There was evidence of mitral valve prolapse (MVP) in 29 (58%) patients and 3 (6%) had evidence of bicuspid aortic valve (BAV). In a control group of 40 age- and sex-matched patients (26 male, 14 female, mean age 29.5 years), who also had heart murmurs but lacked straight upper dorsal spine, only 7 (17.5%) had MVP and none had BAV. The difference is both clinically and statistically significant (p less than 0.001). It is concluded that SBS is more often associated with valvular heart disease (MVP and BAV) than PsHD. Therefore, the diagnosis of SBS should remain presumptive until echocardiography has been performed to exclude MVP and BAV. SBS patients who have valvular heart disease should receive infective endocarditis prophylaxis.

Heart disease in systemic lupus erythematosus: diagnosis and management

Most patients suffering from systemic lupus erythematosus develop secondary heart disease at some time during the course of the primary illness. The most common forms of this type of heart disease are acute fibrinous pericarditis and hypertension. By means of echocardiography, an increased incidence of pericardial effusion has been demonstrated. Although commonly noted at autopsy, myocarditis is often clinically silent. However, endomyocardial biopsy may confirm its presence during life. Libman-Sacks endocarditis, although encountered in 40 to 50% of hearts at autopsy, is rarely diagnosed during life. When significant valve dysfunction such as aortic insufficiency or mitral regurgitation develops during the course of systemic lupus erythematosus, then Libman-Sacks endocarditis should be strongly suspected. Cardiac arrhythmias, first degree AV block, and acquired complete heart block may develop either de novo or in association with lupus pericarditis, myocarditis, vasculitis, etc. Complete congenital heart block has been reported in newborns of mothers with systemic lupus erythematosus, particularly those who have an antibody to a soluble tissue ribonucleoprotein antigen called RO(SS-A). Coronary arteritis and premature coronary atherosclerosis manifesting in either angina pectoris or myocardial infarction in young adults, particularly women suffering from systemic lupus erythematosus, have received attention recently. The development of hypertension and hyperlipidemia while such patients are receiving prolonged corticosteroid therapy has been incriminated as the significant risk factor in premature coronary atherosclerosis. Longstanding hypertension and congestive heart failure have unfavorable prognoses. This report is based on a cumulative review of 50 patients with acute and chronic systemic lupus erythematosus seen at our institution and in private practice during the last 10 years.

Mallory-Weiss syndrome. Experience in a community hospital

The Mallory-Weiss syndrome is characterized by repeated bouts of retching and/or vomiting followed by the sudden onset of hematemesis or melena. Bleeding arises from linear, nonperforating mucosal lacerations at the cardia, cardioesophageal junction, distal esophagus, or a combination of these sites. Hiatal hernia is often a coexisting finding. Severity of hemorrhage can vary from mild to severe (100 to 2,000 ml). The clinical course is usually benign. The diagnosis can be suspected from the history and confirmed by upper gastrointestinal endoscopy. In the majority of patients, medical management controls the bleeding. About 10% to 20% of unselected patients require surgical intervention. With the proper, prompt use of fiberoptic endoscopy in the diagnosis of upper gastrointestinal hemorrhage has come an increase in the number of cases of Mallory-Weiss syndrome being identified. This is true even in community hospitals. The result has been a decrease in surgical intervention and overall mortality.

Rapid differentiation of bacterial meningitides by direct gas-liquid chromatography

Rapid identification of Haemophilus influenzae and other bacillary meningitides was attempted by gas-liquid chromatography (GLC) of the metabolic by-products in broth cultures and in cerebrospinal fluid (CSF) samples obtained from experimental meningitis produced in New Zealand White male rabbits. These results were correlated with the GLC of CSF of meningitis patients. A major peak with retention time of succinic acid was found in the broth cultures of all bacilli tested including H. influenzae, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Proteus mirabilis, Citrobacter freundii, Pseudomonas aeruginosa, and Listeria monocytogenes. Succinic acid was also found in the CSF of experimental meningitis and in the CSF of all patients with H. influenzae and Esch. coli meningitis. This peak was not detected in the blood samples of experimental animals. It was also absent in the broth cultures of all of the gram-positive and gram-negative cocci tested, such as Streptococcus pneumoniae and Neisseria meningitidis. Succinic acid, which appears to be a by product of fermentation, persisted as a clear cut marker in H. influenzae meningitis for at least 3 d after the initiation of treatment. In one patient, the succinic acid peak disappeared during treatment and reappeared with a clinical relapse. Clearly, the presence of succinic acid that can be rapidly detected by GLC in the CSF excludes pneumococcal or meningococcal meningitis and strongly suggests H. influenzae or other bacillary meningitides.