Multifocal hepatic abscesses in immunocompetent patient due to Bartonella henselae: Case report with review of literature

To the best of our knowledge, this is the first case of multifocal hepatic abscesses in a young immunocompetent adult from India, which was successfully treated with hepatectomy and short course of oral antibiotic regimen. Publishing further such case reports will provide more clarity regarding the clinical significance of the disease, including associated risk factors and appropriate treatment.

Mortality due to scrub typhus � report of five cases

Scrub typhus is largely ignored in India particularly during outbreaks of viral fever. The disease course is often complicated leading to fatalities in the absence of treatment. However, if diagnosed early and a specific treatment is initiated, the cure rate is high. We report here five cases of scrub typhus to highlight the fact that high clinical suspicion for such a deadly disease is an absolute necessity.

Distribution of Chlamydia trachomatis omp A genotypes in patients attending a sexually transmitted disease outpatient clinic in New Delhi, India

Background & objectives: Limited data are available on the typing of Chlamydia trachomatis in India. Serovars D to K of C. trachomatis are chiefly responsible for urogenital infections. Thus, this study was conducted to determine the distribution of C. trachomatis serovars in patients with urogenital infections and to characterize omp A gene of the detected C. trachomatis isolates by sequence analysis. Presence of other co-infections was also evaluated. Methods: Endocervical swabs were collected from 324 women and urethral swabs/urine were collected from 193 men attending the sexually transmitted diseases outpatient clinic. The samples were screened for C. trachomatis by cryptic plasmid PCR and omp A gene PCR. Genotyping was performed by PCR-restriction fragment length polymorphism (RFLP) and sequencing of the omp A gene. Samples were screened for genital mycoplasmas, Neisseria gonorrhoeae, Treponema pallidum and human immunodeficiency virus (HIV). Results: C. trachomatis was found in 15.0 per cent men and 10.8 per cent women. Serovar D was the most prevalent followed by serovars E, F, I and G. Twenty two C. trachomatis isolates were selected for omp A gene sequencing. No mixed infection was found. Variability in omp A sequences was seen in 31.8 per cent cases. Both PCR-RFLP and omp A gene sequencing showed concordant results. The presence of Ureaplasma spp. and Mycoplasma hominis was observed in 18.7 and 9.5 per cent patients, respectively. Co-infection of C. trachomatis was significantly associated with Ureaplasma urealyticum and HIV. Interpretation & conclusions: The high occurence of C. trachomatis infections warrants its screening in addition to other sexually transmitted infections namely U. urealyticum and HIV. Genotyping of the omp A gene may provide additional information for vaccine development.

Sonication of antibiotic loaded cement spacers: A valuable technique for detection of infection persistence in two-stage revision for infected joint arthroplasty

We evaluated the diagnostic utility of sonication of antibiotic loaded cement spacers comparing with periprosthetic tissue cultures for the detection of persisting infection in 14 patients undergoing staged procedures. Sonication improved microbial detection of intraoperative cultures from 14.2% to 28.5% (P = 0.481). Routine sonication of spacers is recommended.

Legionella and Legionnaires' disease: Time to explore in India

Legionella pneumophila was first recognised as a fatal cause of pneumonia more than four decades ago, during the 1976-American Legion convention in Philadelphia, USA. Legionella spp. continue to cause disease outbreaks of public health significance, and at present, Legionnaires' disease (LD) has emerged as an important cause of community and hospital-acquired pneumonia. Parallel to this, the understanding of LD has also increased exponentially. However, the disease is likely to be underreported in many countries because of the dearth of common definitions, diagnostic tests and active surveillance systems. In this review, we outline the basic concepts of Legionella including clinical presentations, epidemiology, laboratory diagnosis and the status of LD in India. This article also summarises the progress of research related to Legionella in this country, identifying the research gaps and discussing priorities to explore this unexplored pathogen in India.

Bartonella henselae infection in diverse clinical conditions in a tertiary care hospital in north India

Background & objectives: Bartonella henselae causes infections which closely resemble febrile illness and chronic diseases such as tuberculosis and haematological malignancies. There are not many studies on Bartonella infections from India. The present study was undertaken to diagnose B. henselae infection in diverse clinical conditions in a tertiary care hospital in north India. Methods: A total of 145 patients including those with fever and lymphadenopathy, infective endocarditis and neuroretinitis were enrolled in the study. Whole blood, serum and lymph node aspirate and valvular vegetations if available, were obtained. Samples were plated on chocolate agar and brain-heart infusion agar containing five per cent fresh rabbit blood and were incubated at 35°C for at least four weeks in five per cent CO2with high humidity. Immunofluorescent antibody assay (IFA) was done for the detection of IgM antibodies in the serum using a commercial kit. Whole blood was used to perform polymerase chain reaction (PCR) for the citrate synthase gene (gltA). Results: IFA was positive in 11 of 140 (7.85%) patients and PCR was positive in 3 of 140 (2.14%) patients. Culture was negative in all the cases. A higher incidence of Bartonella infection was seen in patients with fever and lymphadenopathy (n=30), seven of whom were children. In ophthalmological conditions, four cases were IFA positive. Interpretation & conclusions: The present study shows that the threat of Bartonella infection is a reality in India. It is also an important treatable cause of fever and lymphadenopathy in children. Serology and PCR are useful tests for its diagnosis. Clinicians should consider Bartonella infection in the differential diagnosis of febrile illnesses and chronic diseases.

Application of real‑time quantitative polymerase chain reaction assay to detect Legionella pneumophila in patients of community‑acquired pneumonia in a tertiary care hospital.

Legionella pneumophila is one of the important pathogen responsible for community –acquired pneumonia attributing for 1-5% of cases. Since early and accurate therapy reduces mortality, rapid and reliable diagnostic methods are needed. A total of 134 samples of blood, urine and respiratory tract fluids were collected. Blood was tested for IgG, IgM and IgA antibodies using commercially available kits. A total of 8 (6%) samples were found to be positive for L. pneumophila by quantitative reverse transcription polymerase chain reaction (qRT‑PCR), compared to conventional PCR where 6 (4.4%) samples were positive. Serology was positive in a total of 32 (23%) cases though only 3 (2.2%) of the PCR‑positive cases were positive by serology as well. These results suggest that real‑time PCR can detect Legionella infection early in the course of the disease before serological response develops.

Tricky typhus ticks two: A report of two sisters from North India presenting with acute respiratory distress syndrome due to scrub typhus.

Scrub typhus is emerging as an important cause of acute febrile illness in Northern India. This is a report of two sisters presenting concurrently with acute respiratory distress syndrome. A diagnosis of scrub typhus was made in both the patients, and they were successfully treated with doxycycline.

Pathogenesis of Mycoplasma pneumoniae: An update.

Genus Mycoplasma, belonging to the class Mollicutes, encompasses unique lifeforms comprising of a small genome of 8,00,000 base pairs and the inability to produce a cell wall under any circumstances. Mycoplasma pneumoniae is the most common pathogenic species infecting humans. It is an atypical respiratory bacteria causing community acquired pneumonia (CAP) in children and adults of all ages. Although atypical pneumonia caused by M. pneumoniae can be managed in outpatient settings, complications affecting multiple organ systems can lead to hospitalization in vulnerable population. M. pneumoniae infection has also been associated with chronic lung disease and bronchial asthma. With the advent of molecular methods of diagnosis and genetic, immunological and ultrastructural assays that study infectious disease pathogenesis at subcellular level, newer virulence factors of M. pneumoniae have been recognized by researchers. Structure of the attachment organelle of the organism, that mediates the crucial initial step of cytadherence to respiratory tract epithelium through complex interaction between different adhesins and accessory adhesion proteins, has been decoded. Several subsequent virulence mechanisms like intracellular localization, direct cytotoxicity and activation of the inflammatory cascade through toll-like receptors (TLRs) leading to inflammatory cytokine mediated tissue injury, have also been demonstrated to play an essential role in pathogenesis. The most significant update in the knowledge of pathogenesis has been the discovery of Community-Acquired Respiratory Distress Syndrome toxin (CARDS toxin) of M. pneumoniae and its ability of adenosine diphosphate (ADP) ribosylation and inflammosome activation, thus initiating airway inflammation. Advances have also been made in terms of the different pathways behind the genesis of extrapulmonary complications. This article aims to comprehensively review the recent advances in the knowledge of pathogenesis of this organism, that had remained elusive during the era of serological diagnosis. Elucidation of virulence mechanisms of M. pneumoniae will help researchers to design effective vaccine candidates and newer therapeutic targets against this agent.

Antigen sequence typing of outer membrane protein (fetA) gene of Neisseria meningitidis serogroup A from Delhi & adjoining areas.

Background & objectives: Meningitis caused by Neisseria meningitidis is a fatal disease. Meningococcal meningitis is an endemic disease in Delhi and irregular pattern of outbreaks has been reported in India. All these outbreaks were associated with serogroup A. Detailed molecular characterization of N. meningitidis is required for the management of this fatal disease. In this study, we characterized antigenic diversity of surface exposed outer membrane protein (OMP) FetA antigen of N. meningitidis serogroup A isolates obtained from cases of invasive meningococcal meningitis in Delhi, India. Methods: Eight isolates of N. meningitidis were collected from cerebrospinal fluid during October 2008 to May 2011 from occasional cases of meningococcal meningitis. Seven isolates were from outbreaks of meningococcal meningitis in 2005-2006 in Delhi and its adjoining areas. These were subjected to molecular typing of fetA gene, an outer membrane protein gene. Results: All 15 N. meningitides isolates studied were serogroup A. This surface exposed porin is putatively under immune pressure. Hence as a part of molecular characterization, genotyping was carried out to find out the diversity in outer membrane protein (FetA) gene among the circulating isolates of N. meningitidis. All 15 isolates proved to be of the same existing allele type of FetA variable region (VR) when matched with global database. The allele found was F3-1 for all the isolates. Interpretation & conclusions: There was no diversity reported in the outer membrane protein FetA in the present study and hence this protein appeared to be a stable molecule. More studies on molecular characterization of FetA antigen are required from different serogroups circulating in different parts of the world.

Legionella pneumophila infection associated with renal failure causing fatality in a known case of sarcoidosis.

Legionella pneumophila infection may become fatal in immunocompromised state. We report here the first known fatal case from India due to Legionella pneumophila infection complicated by renal failure in a patient undergoing treatment for Sarcoidosis. Sarcoidosis is an idiopathic systemic inflammatory disease involving multiple organs. Urine antigen detection and polymerase chain reaction targeting 16S rRNA gene could help in rapid diagnosis of the infection and thereby start specific therapy. Clinical awareness along with availability of rapid diagnostic tests and institution of specific therapy may reduce morbidity and mortality associated with this infection especially in immunocompromised state.

Serological & molecular approaches for diagnosis of leptospirosis in a tertiary care hospital in north India: A 10-year study.

Background & objectives: Leptospirosis, a spirochetal zoonosis, is underreported from the northern States of India. This study reports results of a 10-year retrospective sero-epidemiological survey of leptospirosis conducted in a tertiary care hospital in New Delhi, India. Method: A total of 1453 patients clinically suspected for leptospirosis were included and investigated initially by IgM ELISA. A proportion of these were subjected to culture, microscopic agglutination test (MAT) and polymerase chain reaction (PCR). Results: Of the 1453 patients, 391 (26.90%) were positive serologically by IgM ELISA. Seropositive and seronegative patients revealed no significant difference in clinical features and laboratory parameters. Amongst the IgM seropositive cases, culture for leptospires was positive in 5 of 192 (2.6%), MAT in 50 of 138 (36.23%), PCR from blood and urine in 10 of 115 (8.7%) and 10 of 38 (26.31%) cases, respectively. In Leptospira spp. positive patients co-infections with viral hepatitis E, malaria and dengue fever were diagnosed in 27 cases. Interpretation & conclusions: The overall seropositivity for leptospirosis was 26.9 per cent in our study. A decreasing trend in seropositivity was observed in recent years. Co-infections with malaria, dengue, hepatitis A and E were also seen. Since leptospirosis is a treatable disease, correct and rapid diagnosis may help in effective management of patients.

Spontaneous cholecysto-cutaneous fistula mimicking postoperative scar sinus.

Although biliary fistulae are common, spontaneous biliary fistulae are very rare. Even more rare are spontaneous cholecysto-cutaneous fistulae. A case of spontaneous cholecysto-cutaneous fistula presenting through an abdominal scar mimicking a postoperative scar sinus is presented, the literature is reviewed and the reasons for occurrence of such a fistula are discussed.

Bioterrorism: a threat for which we are ill prepared.

Of the weapons of mass destruction, the biological ones are the most feared and bioterrorism has become one of the most vicious threats to civilized society in recent times. Biological weapons have been sporadically used for centuries. Despite international regulations, there has been a global re-emergence of the threat of biological warfare. As many as 17 countries are suspected of either including or developing biological agents in their weapons programmes. In the past decade, a number of terrorist organizations with access to bioweapons technology have emerged. Current surveillance systems may be inadequate to detect biological attacks. The onset of illness is often delayed, thus the timing and location of such an event may be extremely difficult to identify. We are unfamiliar with most of the agents of biological warfare and are ill-equipped to handle the consequences of such an attack. In addition, there is no apparent coherent policy to handle a biological terrorist incident. Given the enormity of what is possible in the event of a biological attack, we must be prepared to detect, diagnose, epidemiologically characterize and respond appropriately to biological weapons. Of the potential biological weapons, smallpox and anthrax pose the greatest threats.

Botulism: An update.

Botulism is a paralytic illness caused by the action of a neurotoxin elaborated by Clostridium botulinum. Other clostridial bacteria, like C.butyricum and C.baratii can also produce the toxin leading to signs and symptoms of botulism. Though rare, the illness is potentially fatal and can masquerade as other illnesses making diagnosis difficult. Physicians need to familiarize themselves with the disease as prompt recognition and early treatment can considerably curtail the fatal outcome in the affected and prevent additional cases in the unaffected. New diagnostic, therapeutic and preventive modalities to tackle the disease have come into focus. Botulinum toxin, generally considered a potent poison, is successfully being used for treatment of various neuromuscular disorders representing one of the most dramatic role reversals of modern times.

Infective complications of central venous catheters in cardiac surgical patients.

Prospective randomised study was conducted over a 24 months period in a cardiac surgical intensive care unit to determine the incidence of infection associated with multilumen venous catheters. The influence of various factors including fever, peripheral blood culture, catheter site, catheter usage for monitoring central venous pressure and/inotrope therapy on infection rates were statistically evaluated. A total of 100 catheters submitted to the Microbiology laboratory were bacteriologically examined. Forty-nine of these were inserted into upper body sites, and 51 were inserted into the femoral vein. Twenty-one were triple-lumen catheters. Catheters were removed when a central line was no longer necessary. Catheter tips were cultured by semiquantitative technique for aerobic and anaerobic bacteria. Bacteremia occurred in 3% of catheter insertions; (Enterococcus faecalis, one; Enterobacter spp. One; Acinetobacter spp., one); and catheter colonisation developed in 24%. Neither catheter colonisation nor catheter related infection were associated with any of the risk factors evaluated. Our data indicates that central venous catheters are safe to use in our patients. The inability to identify "risk factors" for catheter infection emphasise the need to maintain a high index of suspicion.