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Featured researches published by George T. John.


Clinical Infectious Diseases | 2005

An immune reconstitution syndrome-like illness associated with Cryptococcus neoformans infection in organ transplant recipients.

Nina Singh; Olivier Lortholary; Barbara D. Alexander; Krishan L. Gupta; George T. John; Kenneth Pursell; Patricia Muñoz; Goran B. Klintmalm; Valentina Stosor; Ramon Del Busto; Ajit P. Limaye; Jyoti Somani; Marshall Lyon; Sally Houston; Andrew A. House; Timothy L. Pruett; Susan L. Orloff; Atul Humar; Lorraine A. Dowdy; Julia Garcia-Diaz; Andre C. Kalil; Robert A. Fisher; Shahid Husain

BACKGROUND We describe an immune reconstitution syndrome (IRS)-like entity in the course of evolution of Cryptococcus neoformans infection in organ transplant recipients. METHODS The study population comprised a cohort of 83 consecutive organ transplant recipients with cryptococcosis who were observed for a median of 2 years in an international, multicenter study. RESULTS In 4 (4.8%) of the 83 patients, an IRS-like entity was observed a median of 5.5 weeks after the initiation of appropriate antifungal therapy. Worsening of clinical manifestations was documented, despite cultures being negative for C. neoformans. These patients were significantly more likely to have received tacrolimus, mycophenolate mofetil, and prednisone as the regimen of immunosuppressive therapy than were all other patients (P = .007). The proposed basis of this phenomenon is reversal of a predominantly Th2 response at the onset of infection to a Th1 proinflammatory response as a result of receipt of effective antifungal therapy and a reduction in or cessation of immunosuppressive therapy. CONCLUSIONS This study demonstrated that an IRS-like entity occurs in organ transplant recipients with C. neoformans infection. Furthermore, this entity may be misconstrued as a failure of therapy. Immunomodulatory agents may have a role as adjunctive therapy in such cases.


The Journal of Infectious Diseases | 2007

Cryptococcus neoformans in Organ Transplant Recipients: Impact of Calcineurin-Inhibitor Agents on Mortality

Nina Singh; Barbara D. Alexander; Olivier Lortholary; Françoise Dromer; Krishan L. Gupta; George T. John; Ramon Del Busto; Goran B. Klintmalm; Jyoti Somani; G. Marshall Lyon; Kenneth Pursell; Valentina Stosor; Patricia Muňoz; Ajit P. Limaye; Andre C. Kalil; Timothy L. Pruett; Julia Garcia-Diaz; Atul Humar; Sally Houston; Andrew A. House; Dannah Wray; Susan L. Orloff; Lorraine A. Dowdy; Robert A. Fisher; Joseph Heitman; Marilyn M. Wagener; Shahid Husain; Corinne Antoine; Barrou Benoît; Anne Elisabeth Heng

Variables influencing the risk of dissemination and outcome of Cryptococcus neoformans infection were assessed in 111 organ transplant recipients with cryptococcosis in a prospective, multicenter, international study. Sixty-one percent (68/111) of the patients had disseminated infection. The risk of disseminated cryptococcosis was significantly higher for liver transplant recipients (adjusted hazard ratio [HR], 6.65; P=.048). The overall mortality rate at 90 days was 14% (16/111). The mortality rate was higher in patients with abnormal mental status (P=.023), renal failure at baseline (P=.028), fungemia (P=.006), and disseminated infection (P=.035) and was lower in those receiving a calcineurin-inhibitor agent (P=.003). In a multivariable analysis, the receipt of a calcineurin-inhibitor agent was independently associated with a lower mortality (adjusted HR, 0.21; P=.008), and renal failure at baseline with a higher mortality rate (adjusted HR, 3.14; P=.037). Thus, outcome in transplant recipients with cryptococcosis appears to be influenced by the type of immunosuppressive agent employed. Additionally, discerning the basis for transplant type-specific differences in disease severity has implications relevant for yielding further insights into the pathogenesis of C. neoformans infection in transplant recipients.


The Journal of Infectious Diseases | 2009

Zygomycosis in Solid Organ Transplant Recipients: A Prospective, Matched Case-Control Study to Assess Risks for Disease and Outcome

Nina Singh; José María Aguado; Hugo Bonatti; Graeme N. Forrest; Krishan L. Gupta; Nasia Safdar; George T. John; Kenneth Pursell; Patricia Muñoz; Robin Patel; Jesús Fortún; Pilar Martín-Dávila; Bruno Philippe; François Philit; Alexis Tabah; Nicolas Terzi; Valérie Chatelet; Shimon Kusne; Nina M. Clark; Emily A. Blumberg; Marino Blanes Julia; Abhi Humar; Sally Houston; Cornelia Lass-Flörl; Leonard B. Johnson; Erik R. Dubberke; Michelle A. Barron; Olivier Lortholary

BACKGROUND Clinical characteristics, risks, and outcomes in solid organ transplant (SOT) recipients with zygomycosis in the era of modern immunosuppressive and newer antifungal agent use have not been defined. METHODS In a matched case-controlled study, SOT recipients with zygomycosis were prospectively studied. The primary outcome measure was success (complete or partial response) at 90 days. RESULTS Renal failure (odds ratio [OR], 3.17; P = .010), diabetes mellitus (OR, 8.11; P < .001), and prior voriconazole and/or caspofungin use (OR, 4.41; P = .033) were associated with a higher risk of zygomycosis, whereas tacrolimus (OR, 0.23; P = .002) was associated with a lower risk of zygomycosis. Liver transplant recipients were more likely to have disseminated disease (OR, 5.48; P = .021) and developed zygomycosis earlier after transplantation than did other SOT recipients (median, 0.8 vs 5.7 months; P < .001). Overall the treatment success rate was 60%. Renal failure (OR, 11.3; P = .023) and disseminated disease (OR, 14.6; P = .027) were independently predictive of treatment failure, whereas surgical resection was associated with treatment success (OR, 33.3; P = .003). The success rate with liposomal amphotericin B was 4-fold higher even when controlling for the aforementioned variables. CONCLUSIONS The risks identified for zygomycosis and for disseminated disease, including those that were previously unrecognized, have implications for further elucidating the biologic basis and for optimizing outcomes in SOT recipients with zygomycosis.


BMC Nephrology | 2012

What do we know about chronic kidney disease in India: first report of the Indian CKD registry

Mohan Rajapurkar; George T. John; Ashok Kirpalani; Georgi Abraham; Sanjay Kumar Agarwal; Alan Fernandes Almeida; Sishir Gang; Amit Gupta; Gopesh K. Modi; Dilip Pahari; Ramdas Pisharody; Jai Prakash; Anuradha S Raman; Devinder Singh Rana; Raj Kumar Sharma; R P Sahoo; Vinay Sakhuja; Ravi Raju Tatapudi; Vivekanand Jha

BackgroundThere are no national data on the magnitude and pattern of chronic kidney disease (CKD) in India. The Indian CKD Registry documents the demographics, etiological spectrum, practice patterns, variations and special characteristics.MethodsData was collected for this cross-sectional study in a standardized format according to predetermined criteria. Of the 52,273 adult patients, 35.5%, 27.9%, 25.6% and 11% patients came from South, North, West and East zones respectively.ResultsThe mean age was 50.1 ± 14.6 years, with M:F ratio of 70:30. Patients from North Zone were younger and those from the East Zone older. Diabetic nephropathy was the commonest cause (31%), followed by CKD of undetermined etiology (16%), chronic glomerulonephritis (14%) and hypertensive nephrosclerosis (13%). About 48% cases presented in Stage V; they were younger than those in Stages III-IV. Diabetic nephropathy patients were older, more likely to present in earlier stages of CKD and had a higher frequency of males; whereas those with CKD of unexplained etiology were younger, had more females and more frequently presented in Stage V. Patients in lower income groups had more advanced CKD at presentation. Patients presenting to public sector hospitals were poorer, younger, and more frequently had CKD of unknown etiology.ConclusionsThis report confirms the emergence of diabetic nephropathy as the pre-eminent cause in India. Patients with CKD of unknown etiology are younger, poorer and more likely to present with advanced CKD. There were some geographic variations.


Clinical Infectious Diseases | 2008

Pulmonary Cryptococcosis in Solid Organ Transplant Recipients: Clinical Relevance of Serum Cryptococcal Antigen

Nina Singh; Barbara D. Alexander; Olivier Lortholary; Françoise Dromer; Krishan L. Gupta; George T. John; Ramon Del Busto; Goran B. Klintmalm; Jyoti Somani; G. Marshall Lyon; Kenneth Pursell; Valentina Stosor; Patricia Muñoz; Ajit P. Limaye; Andre C. Kalil; Timothy L. Pruett; Julia Garcia-Diaz; Atul Humar; Sally Houston; Andrew A. House; Dannah Wray; Susan L. Orloff; Lorraine A. Dowdy; Robert A. Fisher; Joseph Heitman; Marilyn M. Wagener; Shahid Husain

BACKGROUND The role of serum cryptococcal antigen in the diagnosis and determinants of antigen positivity in solid organ transplant (SOT) recipients with pulmonary cryptococcosis has not been fully defined. METHODS We conducted a prospective, multicenter study of SOT recipients with pulmonary cryptococcosis during 1999-2006. RESULTS Forty (83%) of 48 patients with pulmonary cryptococcosis tested positive for cryptococcal antigen. Patients with concomitant extrapulmonary disease were more likely to have a positive antigen test result (P=.018), and antigen titers were higher in patients with extrapulmonary disease (P=.003) or fungemia (P=.045). Patients with single nodules were less likely to have a positive antigen test result than were those with all other radiographic presentations (P=.053). Among patients with isolated pulmonary cryptococcosis, lung transplant recipients were less likely to have positive cryptococcal antigen test results than were recipients of other types of SOT (P=.003). In all, 38% of the patients were asymptomatic or had pulmonary cryptococcosis detected as an incidental finding. Nodular densities or mass lesions were more likely to present as asymptomatic or incidentally detected pulmonary cryptococcosis than as pleural effusions and infiltrates (P=.008). CONCLUSIONS A positive serum cryptococcal antigen test result in SOT recipients with pulmonary cryptococcosis appears to reflect extrapulmonary or more advanced radiographic disease.


Emergency Medicine Journal | 2005

Predictors of multi-organ dysfunction in heatstroke

George M. Varghese; George T. John; Kurien Thomas; Oc Abraham; Dilip Mathai

Background: Heatstroke is a medical emergency that results from failure of thermoregulatory mechanism coupled with an exaggerated acute phase response, causing an elevation in core body temperature that rises above 40°C, producing multi-organ dysfunction. It carries a high mortality rate, and in survivors, a risk of permanent neurological damage. Objective: To investigate predictors of multiple organ dysfunction syndrome in patients presenting with heatstroke. Methods: We investigated 28 patients admitted to a hospital in southern India during the period January 1998 to December 2001. Using a standard form, we collected data on the patients’ characteristics, laboratory data, and outcome, and compared those with multiple organ dysfunction with those without such dysfunction. Results: We found that more than three quarters of the studied patients developed multiple organ dysfunction, with the most common dysfunction being respiratory failure. Among the selected predictors, metabolic acidosis 14 of 16 patients, 87.5%; p = 0.011, elevated CPK 17 of 19 patients, 89.5%; p = 0.005, and liver enzymes elevated more than twice the normal (11 of 18 patients, 61%; p = 0.02) had the highest correlation with dysfunction of two or more organs. Conclusions: The high mortality observed in heatstroke is secondary to multi-organ dysfunction, and among the various parameters assessed, high levels of CPK (>1000 IU/l), metabolic acidosis, and elevated liver enzymes are predictive. Aggressive measures to lower the body temperature with other supportive therapy could substantially reduce the mortality.


Antimicrobial Agents and Chemotherapy | 2008

Calcineurin Inhibitor Agents Interact Synergistically with Antifungal Agents In Vitro against Cryptococcus neoformans Isolates: Correlation with Outcome in Solid Organ Transplant Recipients with Cryptococcosis

Dimitrios P. Kontoyiannis; Russell E. Lewis; Barbara D. Alexander; Olivier Lortholary; Françoise Dromer; Krishan L. Gupta; George T. John; Ramon Del Busto; Goran B. Klintmalm; Jyoti Somani; G. Marshall Lyon; Kenneth Pursell; Valentina Stosor; Patricia Muňoz; Ajit P. Limaye; Andre C. Kalil; Timothy L. Pruett; Julia Garcia-Diaz; Atul Humar; Sally Houston; Andrew A. House; Dannah Wray; Susan L. Orloff; Lorraine A. Dowdy; Robert A. Fisher; Joseph Heitman; Nathaniel D. Albert; Marilyn M. Wagener; Nina Singh

ABSTRACT Synergistic interactions were observed between CIs and antifungal agents against 53 (90%) of 59 Cryptococcus neoformans isolates from solid organ transplant recipients with cryptococcosis and may account for better outcomes in patients with cryptococcosis receiving these immunosuppressive agents.


Transplantation | 2004

Leflunomide Therapy For Cytomegalovirus Disease In Renal Allograft Recepients

George T. John; Jothi Manivannan; Sara Chandy; Shajan Peter; Chakko K. Jacob

Leflunomide has excellent antiviral activity against cytomegalovirus (CMV) in animal models and is considerably less expensive than intravenous ganciclovir. We used leflunomide in four consenting renal allograft recipients with symptomatic CMV disease, who were unable to afford ganciclovir and would otherwise remain untreated. This is the first report of efficacy of leflunomide in humans with CMV disease. They received loading dose of 100 mg of leflunomide once daily on days 1–3 and then 20 mg once daily for 3 months. All four patients were followed up three times weekly with physical examination, total leukocyte counts, blood urea and serum creatinine for a minimum period of 6 weeks. None of the patients showed drug related adverse events, alteration in cyclosporine levels, or decreased graft function, except one who developed leucopenia. Preliminary data presented suggests that leflunomide therapy for CMV disease is effective and could be used with careful monitoring in allograft recipients who cannot afford intravenous ganciclovir therapy. The duration of treatment and the role of leflunomide in secondary prophylaxis and in situations of ganciclovir resistance need to be studied further.


Transplantation | 2005

Antifungal management practices and evolution of infection in organ transplant recipients with cryptococcus neoformans infection.

Nina Singh; Olivier Lortholary; Barbara D. Alexander; Krishan L. Gupta; George T. John; Kenneth Pursell; Patricia Muñoz; Goran B. Klintmalm; Valentina Stosor; Ramon Del Busto; Ajit P. Limaye; Jyoti Somani; Marshall Lyon; Sally Houston; Andrew A. House; Timothy L. Pruett; Susan L. Orloff; Atul Humar; Lorraine A. Dowdy; Julia Garcia-Diaz; Andre C. Kalil; Robert A. Fisher; Joseph Heitman; Shahid Husain

Background. Therapeutic practices for Cryptococcus neoformans infection in transplant recipients vary, particularly with regards to antifungal agent employed, and duration of therapy. The risk of relapse and time to recurrence is not known. We assessed antifungal treatment practices for cryptococcosis in a cohort of prospectively followed organ transplant recipients. Methods. The patients comprised 83 transplant recipients with cryptococcosis followed for a median of 2.1 and up to 5.2 years. Results. Patients with central nervous system infection (69% vs. 16%, P = 0.00001), disseminated infection (82.7% vs. 20%, P = 0.00001), and fungemia (29% vs. 8%, P = 0.046) were more likely to receive regimens containing amphotericin B than fluconazole as primary therapy. The use of fluconazole, on the other hand, was more likely for infection limited to the lungs (64% vs. 14%, P = 0.00002). Survival at 6 months tended to be lower in patients whose CSF cultures at 2 weeks were positive compared to those whose CSF cultures were negative (50% vs. 91%, P = 0.06). Maintenance therapy was employed in 68% (54/79) of the patients who survived >3 weeks. The median duration of maintenance therapy was 183 days; 55% received maintenance for ≥ 6 months and 25% for >1 year. Relapse was documented in 1.3% (1/79) of the patients. Conclusions. A majority of the organ transplant recipients with cryptococcosis receive maintenance antifungal therapy for 6 months with low risk of relapse. These data can assist in trials to assess the optimal therapeutic approach and duration of therapy for cryptococcosis in transplant recipients.


American Journal of Transplantation | 2009

Pulmonary zygomycosis in solid organ transplant recipients in the current era.

Hsin-Yun Sun; José María Aguado; Hugo Bonatti; Graeme N. Forrest; Krishan L. Gupta; Nasia Safdar; George T. John; Kenneth Pursell; Patricia Muñoz; Robin Patel; Jesús Fortún; Pilar Martín-Dávila; B. Philippe; F. Philit; Alexis Tabah; Nicolas Terzi; V. Chatelet; Shimon Kusne; Nina M. Clark; Emily A. Blumberg; Marino Blanes Julia; Abhinav Humar; S. Houston; Cornelia Lass-Flörl; Leonard B. Johnson; Erik R. Dubberke; Michelle A. Barron; O. Lortholary; Nina Singh

Fifty‐eight solid organ transplant recipients with zygomycosis were studied to assess the presentation, radiographic characteristics, risks for extra‐pulmonary dissemination and mortality of pulmonary zygomycosis. Pulmonary zygomycosis was documented in 31 patients (53%) and developed a median of 5.5 months (interquartile range, 2–11 months) posttransplantation. In all, 74.2% (23/31) of the patients had zygomycosis limited to the lungs and 25.8% (8/31) had lung disease as part of disseminated zygomycosis; cutaneous/soft tissue (50%, 4/8) was the most common site of dissemination. Pulmonary disease presented most frequently as consolidation/mass lesions (29.0%), nodules (25.8%) and cavities (22.6%). Patients with disseminated disease were more likely to have Mycocladus corymbifer as the causative pathogen. The mortality rate at 90 days after the treatment was 45.2%. In summary, pulmonary zygomycosis is the most common manifestation in solid organ transplant recipients with zygomycosis, and disseminated disease often involves the cutaneous/soft tissue sites but not the brain.

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Chakko K. Jacob

Christian Medical College

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Gopal Basu

Christian Medical College

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Bs Mathew

Christian Medical College

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L. Jeyaseelan

Christian Medical College

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V. Tamilarasi

Christian Medical College

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