Clinical and histological discrepancies in diagnosis of ENL reactions classified by assessment of acute phase proteins SAA and CRP

Sixteen out of 45 (36%) leprosy patients with clinical features of acute erythema nodosum leprosum (ENL) did not show the characteristic presence of neutrophils (polymorphs) in histology of the ENL lesion. The acute-phase reactants, serum amyloid A (SAA) and C-reactive protein (CRP) which are systemic markers of inflammation, and IgM and IgG antibody to Mycobacterium leprae were determined in these patients in order to understand the differences in histological diagnosis. Both SAA and CRP were elevated in ENL patients, irrespective of the presence of polymorph infiltrates, as compared to nonreactional lepromatous patients, patients with histologically confirmed reversal reactions and endemic controls, indicating that all clinically diagnosed ENL patients had ongoing inflammatory reactions. On the other hand, IgM and IgG antibodies were significantly lower (> 70%) in ENL patients as compared to nonreactional lepromatous patients. When the two ENL groups [ENL-PMN+ve (positive for neutrophils) and ENL-PMN-ve (negative for neutrophils)] were compared, there were no significant differences in the mean SAA, IgM or IgG antibody concentrations, but CRP was eightfold lower in ENL-PMN-ve as compared to the ENL-PMN+ve group. This may indicate that the timing or modulation of the reaction was different in the two ENL groups. Thus, measurement of the acute-phase response and the ratio of SAA/CRP in particular are helpful in the clinical diagnosis of ENL reactions in leprosy.

Immunoglobulin G1 (IgG1) and IgG3 antibodies are markers of progressive disease in leprosy

Mycobacterium leprae-specific and polyclonal immunoglobulin G (IgG) subclass and IgE antibodies in leprosy patients across the histopathological spectrum were determined by using a quantitative enzyme-linked immunosorbent assay. Antibody responses to M. leprae sonicates were detected only in IgG1, -2, and -3 subclasses. Even at 100-times-lower dilutions, very little IgG4 and IgE antibody activity against M. leprae was detected in any group of leprosy patients. Quantitatively, antibody responses were highest at the lepromatous pole and decreased towards the tuberculoid pole. The greatest quantitative difference in antibodies between the lepromatous and tuberculoid poles was observed with IgG1 (140-fold), this was followed by the difference with IgG3 antibodies (32-fold). Polyclonal antibodies, on the other hand, were elevated for all four IgG subclasses as well as IgE in both lepromatous and tuberculoid leprosy patients compared with healthy controls from a leprosy-endemic area. Selective elevation of M. leprae-specific antibody responses in IgG1 and IgG3 subclasses, therefore, could not be attributed to selective polyclonal activation in these particular subclasses. Furthermore, polyclonal activation for IgE was observed in both lepromatous and tuberculoid leprosy patients, with higher levels in the tuberculoid group, which does not support selective TH2 activation in lepromatous leprosy patients. IgG1 and IgG3 antibodies also showed the highest Spearman rank correlation with the bacterial index in these patients (rho = 0.748 and P < 0.001 for IgG1; rho = 0.721 and and P < 0.001 for IgG3). Thus, disease progression in leprosy showed a significant correlation with selective increases in IgG1 and IgG3 responses.

Recognition of Mycobacterium leprae recombinant 18,000 MW epitopes by IgG subclasses in leprosy

IgG subclasses are known to be differentially regulated by cytokines (elaborated by activated T cells), which act as growth factors and immunoglobulin switch factors on B cells. In leprosy, we have previously shown that IgG subclass antibodies to a purified recombinant antigen of Mycobacterium leprae (18,000 MW) are restricted to IgG1 and IgG3 across the disease spectrum. The only significant difference observed was that lepromatous patients with low to undetectable T-cell responses showed a strong correlation between IgG1 and IgG3 (P < 0.001) antibodies while tuberculoid patients who showed strong T-cell responses did not show such a correlation. To examine if these differences were related to T-cell-mediated class switching in tuberculoid leprosy patients, we have studied epitope recognition by IgG1 and IgG3 using a panel of synthetic peptides spanning the 18,000 MW molecule in an enzyme-linked immunosorbent assay (ELISA). In lepromatous patients there was little similarity in peptide recognition by IgG1 and IgG3, with IgG1 recognition being restricted to a single dominant carboxy-terminal peptide while the IgG3 antibodies recognized a diverse set of peptides in the N-terminal half of the 18,000 MW molecule. In tuberculoid patients both IgG1 and IgG3 antibody showed recognition of similar peptides in the N-terminal half of the 18,000 MW molecule. Our results therefore support the hypothesis that immunoglobulin class switching is occurring in tuberculoid but not in lepromatous patients.

Aortic arch dissection from patent ductus arteriosus

An unusual case of aortic arch dissection from a patent ductus arteriosus (PDA) is described. An adult man had been diagnosed as suffering from pectus excavatum and PDA 10 years before. At that time the pectus was repaired, but he failed to return for surgery on the PDA and the sub-sternal strut for pectus repair was also never removed. Recently he was admitted in a peripheral hospital with chest infection. Patent ductus arteriosus murmur was audible on clinical examination. The chest X-ray showed a widened mediastinum and the pectus strut. On further investigations dissection of the aortic arch was discovered and arch replacement performed.

Role of beta-adrenergic mechanisms in exercise training-induced metabolic changes in respiratory and locomotor muscle

To test the hypothesis that beta-adrenergic stimulation is required for the normal increase in oxidative capacity of respiratory and locomotor skeletal muscle in response to exercise training, we examined the effects of beta-blockade on muscle oxidative capacity in trained and sedentary rats. Thirty-four female adult Sprague-Dawley rats were randomly divided into four experimental groups: 1) trained+propranolol (TP); 2) trained + sham injection (TS); 3) sedentary + propranolol (SP); and 4) sedentary + sham injection (SS). Training increased (p < 0.05) citrate synthase (CS) activity in the plantaris (+29%) and costal diaphragm (+12%) of TS animals compared to SS animals. In contrast, training did not (p > 0.05) increase costal diaphragm CS activity in TP animals compared to the SS group. Further, although training increased (p < 0.05) plantaris CS activity in the TP group (+18%) compared to the SP group, the training-induced increase in muscle CS activity was 11% lower (p < 0.05) than observed in TS animals. Collectively, these results suggest that beta-adrenergic mechanisms may play a role in the normal training-induced increase in oxidative capacity in both respiratory and locomotor skeletal muscles.

A colorimetric PCR method for the detection of M. leprae in skin biopsies from leprosy patients

A one-tube nested polymerase chain reaction (PCR) method for the diagnosis of paucibacillary leprosy was developed using the repetitive RLEP sequence as a target. Detection of the PCR products was simplified by the adaptation of a colorimetric method. The test was specific for Mycobacterium leprae, and the sensitivity of the assay was 1 fg of purified genomic M. leprae DNA (less than one genome). Complete concordance was seen between the development of color and resolution on agarose gels. The results of frozen skin sections from untreated patients showed that the assay could detect 100% of multibacillary samples [bacterial index (BI) of 2 or more] and 69% and 70% of the samples with BIs of 1 and 0, respectively. The use of one-tube nested PCR in assessing the effectiveness of multidrug therapy (MDT) in leprosy also was determined. The simplified colorimetric assay was found to be sensitive, rapid and specific, and is suitable for use in routing diagnostic laboratories.

IgG subclass antibody to Mycobacterium leprae 18,000 MW antigen is restricted to IgG1 and IgG3 in leprosy

IgG subclass responses to Mycobacterium leprae 18,000 MW recombinant antigen (18K) were determined in sera from untreated leprosy patients using an ELISA-based assay with specific monoclonal antibodies. Antibodies to M. leprae 18K were restricted to IgG1 and IgG3 antibodies with higher seropositivity in lepromatous patients (25.5% for IgG1 and 12.8% for IgG3) compared to patients with tuberculoid disease (11.5% for IgG1 and 5% for IgG3). No significant antibody response was detectable in IgG2 and IgG4 in patients with either lepromatous or tuberculoid leprosy. The selective production of antibodies in IgG1 and IgG3 subclasses could not be related to polyclonal activation in these subclasses as all IgG subclasses showed similar elevated levels at the polyclonal level. The major difference noted between lepromatous and tuberculoid leprosy patients with the IgG subclass antibody response was a strong linear correlation between IgG1 and IgG3 responses to M. leprae 18K in lepromatous patients (r = 0.703, P < 0.001) but not in tuberculoid leprosy patients (r = 0.007, P > 0.10) which may be related to immunoglobulin class switching of IgG3 to IgG1 rather than selective shifts in T-helper subsets. Our results therefore, do not support the hypothesis that activation of Th2 cells occurs in lepromatous leprosy; this issue needs further examination.

Once weekly subcutaneous administration of erythropoietin in haemodialysis patient

Twenty-five anaemic patients of End Stage Renal Disease (ESRD) on maintenance haemodialysis at the Kidney Centre were studied. Recombinant human erythropoietin (EPO) 50-units/kg body weight was given once a week subcutaneously to see the response to therapy. In 21 cases haemoglobin increased significantly from 7.5 to 9.5 g/dl and haematocrit from 23 to 30.5 l/l with success rate of 84% and marked improvement in their quality to life. Once a week subcutaneous administration of erythropoietin is convenient and cost effective in reversing renal anaemia with minimal complications.

Risk factors for intrauterine growth retardation: results of a community-based study from Karachi

There is a serious lack of community-based information on low birthweight or intrauterine growth retardation from Pakistan. A community based prospective study was conducted in four squatter settlements of Karachi, to examine the prevalence and risk factors for adverse pregnancy outcome. This paper reports on the prevalence and risk factors for intrauterine growth retardation (<10th percentile birthweight gestational age) among 755 singleton births. The incidence of intrauterine growth retardation was 25.4% (192 intrauterine growth retarded and 563 appropriate for gestational age). Major socioeconomic risk factors identified were low maternal education (RR = 1.4, 95% CI = 1.0,2.1) and poor housing material (RR = 1.7, 95% CI = 1.0,3.0). Among the significant biologic factors, primiparity (RR = 1.9, 95% CI = 1.4,2.7), consanguinity (RR = 1.4, 95% CI = 1.4,2.7), consanguinity (RR = 1.4, 95% CI = 1.1,1.8), short birth to CI = 1.1,2.1), short stature (RR = 2.2, 95% CI = 1.6,3.0), low maternal weight (RR = 2.0, 95% CI = 1.6,2.5) and non-vegetarian diet (RR = 2.3, 95% CI = 1.3,4.2) were especially important. Investigations to assess the adverse mortality and morbidity effects of intrauterine growth retardation are ongoing.

An RFLP map for 2q33-q37 from multicase mycobacterial and leishmanial disease families: no evidence for an Lsh/Ity/Bcg gene homologue influencing susceptibility to leprosy

The mycobacterial diseases leprosy and tuberculosis (TB) and the leishmaniases are characterized by a wide spectrum of disease phenotypes, and by the fact that the majority of individuals exposed to the causative organisms Mycobacterium leprae, M. tuberculosis and Leishmania sp. become infected but do not present with clinical disease. In order to determine whether a human homologue to the murine macrophage resistance gene Lsh/Ity/Bcg influences susceptibility to human disease, multicase families for all three diseases have been collected, and linkage analysis performed using a panel of markers in the region of human chromosome 2q33-q37 known to be conserved with the Lsh/Ity/Bcg-containing region of murine chromosome 1. Because of the paucity of available polymorphic markers/linkage information for 2q33-q37, data from 35 multicase leprosy, TB and visceral leishmaniasis families (310 individuals) were first pooled to produce a detailed RFLP map of the region. Peak LOD scores well in excess of 3 were observed for linkage between adjacent pairs of a more proximal (2q33-q35) set of markers CRYGP1, MAP2, FN1, TNP1, VIL1 and DES, and between adjacent pairs of a more distal (2q35-q37) set COL6A3, D2S55 and D2S3. These peak LOD scores and the corresponding values for theta were used in the MAP92 program to generate a multiple two-point map with gene order/map intervals (cM) of: CRYGP1-4.65-MAP2-3.45-FN1-5.95-TNP1-3.41-VIL1-3. 01- DES-20.14-COL6A-10.91-D2S55-3.67-D2S3. Although local support for the placement of loci in this order was weak (LOD < 2, except for DES-COL6A3 where LOD = 6.02), the map is consistent with the gene order for those loci (Cryg, Fn-1, Tp-1, Vil, Des, Col6a3) previously mapped in the mouse. Data from 17 multicase leprosy families (149 individuals) were further analysed for linkage between a putative disease susceptibility locus (DSL) controlling susceptibility to leprosy per se and each of the marker loci. Assuming 100% penetrance for the susceptibility allele, no positive LOD score was obtained for linkage between the DSL and any of the marker genes. Instead, the data provide convincing evidence (LOD scores < -2) that a DSL does not fall within 10-20 cM of CRYGP1, MAP2, TNP1, VIL1, DES or D2S55, or within 5-10 cM of FN1, COL6A3 or D2S3. This effectively excludes a putative DSL controlling susceptibility to leprosy per se from the entire region 2q33-q37.(ABSTRACT TRUNCATED AT 400 WORDS)

Antigen-coated latex particles as a model system for probing monocyte responses in leprosy

To study responses to Mycobacterium leprae antigens, we developed an in vitro model system in which latex particles coated with M. leprae sonic extract (MLSON) antigen were presented to monocytes. Uptake and oxidative response as measured by superoxide production to these antigens were investigated. Phagocytosis of MLSON-coated particles was greater than that of control particles in monocytes from both leprosy patients and controls from leprosy-endemic areas; uptake of MLSON-coated particles was higher in monocytes from lepromatous leprosy patients than in cells from tuberculoid leprosy patients and controls. In both patients and controls, uptake of latex particles coated with leprosy antigens triggered very little reduction of nitroblue tetrazolium although the cells were capable of mounting a respiratory burst. Antigen-coated latex particles can therefore be used as a tool to investigate monocyte responses to M. leprae and individual recombinant antigens.

Metastatic malignant schwannoma in the heart

A rare case of metastatic malignant schwannoma is described. The secondary tumor in the right lung grew along the pulmonary vein and filled almost the whole of left atrium. Operation was later performed, and a large tumor extension from the left atrium was removed.

Use of polymerase chain reaction to assess efficacy of leprosy chemotherapy

The assessment of chemotherapy efficacy in leprosy is difficult, since the only reliable method for determining whether the causative organism, Mycobacterium leprae, is viable depends on its growth in mouse foot pads. In an attempt to replace this expensive, time-consuming test, methods based on the polymerase chain reaction (PCR) have been developed. These methods depend on detection of DNA, which is more susceptible to degradation on cell death than are other cell components, so should be a more accurate indicator of viability. We have used a specific PCR assay to detect M leprae DNA in skin biopsy samples from leprosy patients. By use of limiting dilution PCR (LD-PCR), the concentration of M leprae DNA in the original sample could be measured. The DNA concentration was more closely correlated with the morphological index (derived from a staining technique that distinguishes morphologically intact and damaged bacteria) than with the number of bacteria visible (bacterial index, BI, which counts both alive and dead bacteria). In a longitudinal study of multibacillary patients on multi-drug therapy, skin biopsy samples were collected before treatment and 3, 6, 12, and 24 months after the start of therapy. While the BI showed little or no change during treatment, the number of genomes detected by PCR fell sharply, in parallel with the MI. We propose that PCR can be used as a rapid measure of M leprae viability and that this approach can be used for monitoring individual leprosy patients and for assessment of existing and new regimens. The method may be applicable to other infectious diseases in which culture of the causative organism is slow or impossible.

The value of intermittent growth monitoring in primary health care programmes

The objective of growth monitoring is to detect early growth faltering before the child becomes severely malnourished. It has been found in many large projects in the private sector and in Government run Primary Health Care (PHC) programmes that monthly weighing is not feasible which makes it impossible to develop a functional outreach programme on a sustainable basis. This study is an attempt to propose an intermittent growth monitoring which is operationally feasible for large scale PHC programmes in the public sector. A historical prospective study was conducted to find out the correlation of weights of children at different ages with weights at subsequent months. Two hundred and ninety-two growth cards of children were selected from two squatter settlements of Karachi which are having a PHC programme through the Aga Khan University. At six months, about 71% of children were within the normal range, with increasing age from 10% to 39% of these children shifted to grade I Protein Energy Malnutrition (PEM). When weights of children for each month were correlated with weights at all other months up to 24 months, it was found that correlation coefficient at 6th and 9th month were significant (P value < 0.001). Probability of developing malnutrition at different weights and ages were also calculated. The results indicate that malnutrition starts appearing at 6 months and weights at 6 months and to a lesser extent at 9 months are better prognostic indices of future malnutrition. Intermittent weighing of children can help in early identification of "high risk" children who can then be managed and even be prevented from developing future malnutrition.

Sequence and immunological characterization of a serine-rich antigen from Mycobacterium leprae

Sera from lepromatous leprosy patients were used to screen a Mycobacterium leprae lambda gt11 library. Three positive plaques were picked, and lysogens were constructed. Immunoblot analysis showed that all of the lysogens expressed an apparently identical beta-galactosidase fusion protein which reacted strongly with the sera. The 1.7-kbp insert from one clone was subcloned into the lacZ gene in pUR290; sequence analysis of the end fused to lacZ revealed an open reading frame with no significant homology to previously published sequences. The insert was used to screen an M. leprae cosmid library, and five clones were isolated. The insert was also found to hybridize to clones expressing the M. leprae antigen which had previously been designated class III and 25L. A 1.8-kbp HindIII fragment was subcloned from one of the cosmids and sequenced. The sequence revealed a 1,227-bp open reading frame, encoding a 408-amino-acid protein with a predicted molecular mass of 42,466 Da. The protein contains amino- and carboxy-terminal hydrophobic domains and a hydrophilic central domain; the amino-terminal domain shows some homology to a 51-kDa hypothetical antigen of Mycobacterium tuberculosis, while the hydrophilic region contains a high proportion of serine residues, and we have therefore designated the protein serine-rich antigen (Sra). Some repeated motifs are present in the protein, but their significance is unknown. Seventy-eight percent of serum samples from multibacillary leprosy patients and 68% of serum samples from paucibacillary leprosy patients recognized the fusion protein, showing that this is a major M. leprae antigen. In contrast, all serum samples from endemic controls were negative, while 26% of serum samples from tuberculosis patients were weakly positive.

Systemic lupus erythematosus a rare cause of mitral stenosis

An unusual case of mitral stenosis in a patient with Systemic Lupus Erythematosus (SLE) is presented. A middle aged lady, known to be suffering from SLE, was initially suspected to have left atrial myxoma. Only during surgery was the true rare pathology discovered: the valve was excised and replaced with a mechanical prosthesis.

Systemic manifestations of invasive amebiasis

Eighty-four patients with serious infection due to Entamoeba histolytica were evaluated for systemic complications by objective criteria for dysfunction of the organ systems normally assessed in surgical sepsis. Of 71 patients with amebic liver abscess (ALA), 41% had systemic complications and 13% had more than one organ system involved. Patients > or = 40 years of age and those being treated with steroids were at significantly increased risk of developing complications (P < or = .05). The erythrocyte sedimentation rate and the levels of the acute-phase markers C-reactive protein (CRP) and serum amyloid A (SAA) were significantly elevated in patients with ALA over values in those without ALA (P < or = .05). ALA patients with complications had lower CRP and SAA concentrations than those without complications (P < or = .05). Blood and liver aspirates in ALA patients were usually bacteriologically sterile. The pathogenesis of systemic complications and the associated acute-phase response requires further study, and ways of predicting disease severity and intervening therapeutically must be devised.

Intraocular pressure decrease in household contacts of patients with Hansen's disease and endemic control subjects

We compared the intraocular pressure in 150 urban household contacts of patients with Hansen's disease and 132 endemic control subjects from an urban population in Karachi, Pakistan, who were matched in regard to race, age, gender, and socioeconomic status. The mean intraocular pressure in the upright position was 12.6 mm Hg in the right eye and 12.9 mm Hg in the left eye in household contacts of patients with Hansen's disease and 15.3 mm Hg in the right eye and 15.4 mm Hg in the left eye in the endemic control population (P < .0005). The postural change in intraocular pressure from the upright to supine position was 1.7 mm Hg in the right eye and 2.1 mm Hg in the left eye in the household contacts group and 1.3 mm Hg in the right eye and 1.5 mm Hg in the left eye in the endemic control group (P < .0006). Our findings, especially in view of past observations in intraocular pressure changes in patients with Hansen's disease, raise serious questions about possible early ocular susceptibility to Mycobacterium leprae infection and about public health issues, including possible early indication of disease.

Recognition of Mycobacterium leprae recombinant 18-kDa proteins in leprosy

Three different, purified, Escherichia coli-derived, recombinant preparations of the Mycobacterium leprae 18K protein were compared for their immunological recognition in leprosy. The preparations tested were 18K fusion proteins containing 70% (amino acids 38-148) of the full 18K protein fused to either a short leader sequence containing six asparagine residues or to beta-galactosidase, and the full length 18K protein. All three recombinant antigens were recognized by IgG antibodies which were restricted mostly to lepromatous leprosy patients. The 18K antigen with the asparagine leader sequence showed better reactivity with IgG antibodies compared with the other two 18K preparations. In lymphocyte proliferation assays, the truncated 18K and the full-length 18K showed equivalent responses in the same donors with strongest recognition in donors who were also strongly responsive to the M. leprae soluble sonicate. These results indicate that the major human B- and T-cell epitopes are located within the segment 38-148, although some individuals may recognize additional epitopes at the NH2-terminal end.