High Prevalence of Pneumocystis jirovecii Dihydropteroate Synthase Gene Mutations in Patients with a First Episode of Pneumocystis Pneumonia in Santiago, Chile, and Clinical Response to Trimethoprim-Sulfamethoxazole Therapy

ABSTRACT Mutations in the dihydropteroate synthase (DHPS) gene of Pneumocystis jirovecii are associated with the failure of sulfa prophylaxis. They can develop by selection in patients receiving sulfa drugs or be acquired via person-to-person transmission. DHPS mutations raise concern about the decreasing efficacy of sulfa drugs, the main available therapeutic tool for Pneumocystis pneumonia (PCP). The prevalence of Pneumocystis DHPS mutations was examined in Pneumocystis isolates from 56 sulfa-prophylaxis-naive adults with a first episode of PCP from 2002 to 2010 in Santiago, Chile. Their clinical history was reviewed to analyze the effect of these mutations on response to trimethoprim-sulfamethoxazole (TMP-SMX) therapy and outcome. Mutant genotypes occurred in 22 (48%) of 46 HIV-infected patients and in 5 (50%) of 10 HIV-uninfected patients. Compared to patients with a wild-type genotype, those with mutant genotypes were more likely to experience sulfa treatment-limiting adverse reactions and to have a twice-longer duration of mechanical ventilation if mechanically ventilated. Specific genotypes did not associate with death, which occurred in none of the HIV-infected patients and in 50% of the non-HIV-infected patients. Chile has a high prevalence of DHPS mutations, which were presumably acquired through interhuman transmission because patients were not on sulfa prophylaxis. These results contrast with the low prevalence observed in other Latin American countries with similar usage of sulfa drugs, suggesting that additional sources of resistant genotypes may be possible. The twice-longer duration of mechanical ventilation in patients with mutant DHPS genotypes suggests a decreased efficacy of TMP-SMX and warrants collaborative studies to assess the relevance of DHPS mutations and further research to increase therapeutic options for PCP.

[1]  M. Thon,et al.  Identification of horizontally transferred genes in the genus Colletotrichum reveals a steady tempo of bacterial to fungal gene transfer , 2015, BMC Genomics.

[2]  C. Prigent-Combaret,et al.  Frequent, independent transfers of a catabolic gene from bacteria to contrasted filamentous eukaryotes , 2014, Proceedings of the Royal Society B: Biological Sciences.

[3]  C. Beard,et al.  Dihydropteroate synthase mutations in Pneumocystis pneumonia: impact of applying different definitions of prophylaxis, mortality endpoints and mutant in a single cohort. , 2013, Medical mycology.

[4]  P. Walzer,et al.  Pneumocystis pneumonia associated with human immunodeficiency virus. , 2013, Clinics in chest medicine.

[5]  Patrick Taffé,et al.  Pneumocystis jirovecii Genotype Associated with Increased Death Rate of HIV-infected Patients with Pneumonia , 2013, Emerging infectious diseases.

[6]  Ángel González,et al.  Molecular diagnosis and detection of Pneumocystis jirovecii DHPS and DHFR genotypes in respiratory specimens from Colombian patients. , 2012, Diagnostic microbiology and infectious disease.

[7]  W. TeresaBeroíza,et al.  Etiología de la neumonía en pacientes chilenos infectados por el virus de la inmunodeficiencia humana , 2011 .

[8]  F. LuisBavestrello,et al.  Consumo comunitario de antimicrobianos en Chile, 2000-2008 , 2011 .

[9]  O. Matos,et al.  Epidemiology and clinical relevance of Pneumocystis jirovecii Frenkel, 1976 dihydropteroate synthase gene mutations. , 2010, Parasite.

[10]  P. Francioli,et al.  Interhuman transmission as a potential key parameter for geographical variation in the prevalence of Pneumocystis jirovecii dihydropteroate synthase mutations. , 2010, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[11]  S. Meshnick,et al.  Low Prevalence of Pneumocystis pneumonia (PCP) but High Prevalence of Pneumocystis dihydropteroate synthase (dhps) Gene Mutations in HIV-Infected Persons in Uganda , 2010, PLoS ONE.

[12]  J. Boyer,et al.  Linking Pneumocystis jiroveci sulfamethoxazole resistance to the alleles of the DHPS gene using functional complementation in Saccharomyces cerevisiae. , 2010, Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.

[13]  R. Gonzales,et al.  Trends in antibiotic utilization in eight Latin American countries, 1997-2007. , 2010, Revista panamericana de salud publica = Pan American journal of public health.

[14]  Sergio L Vargas,et al.  Pneumocystis colonization is highly prevalent in the autopsied lungs of the general population. , 2010, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[15]  M. LauraBahamondes,et al.  Características de la neumonía por Pneumocystis jiroveci en adultos con SIDA con y sin terapia antiretroviral , 2006 .

[16]  J. Prolla,et al.  Absence of Dihydropteroate Synthase Mutations in Pneumocystis jirovecii from Brazilian AIDS Patients , 2006, The Journal of eukaryotic microbiology.

[17]  C. Beard,et al.  Severity and outcome of HIV-associated Pneumocystis pneumonia containing Pneumocystis jirovecii dihydropteroate synthase gene mutations , 2005, AIDS.

[18]  S. SaraChernilo,et al.  Lung diseases among HIV infected patients admitted to the "Instituto Nacional del Torax" in Santiago, Chile , 2005 .

[19]  P. Vanhems,et al.  Molecular Evidence of Interhuman Transmission of Pneumocystis Pneumonia among Renal Transplant Recipients Hospitalized with HIV-Infected Patients , 2004, Emerging infectious diseases.

[20]  S. Meshnick,et al.  Sulfa Use, Dihydropteroate Synthase Mutations, and Pneumocystis jirovecii Pneumonia , 2004, Emerging infectious diseases.

[21]  Kristina Crothers,et al.  Dihydropteroate Synthase Gene Mutations in Pneumocystis and Sulfa Resistance , 2004, Emerging infectious diseases.

[22]  F. Cabello [Antibiotics and aquaculture in Chile: implications for human and animal health]. , 2004, Revista medica de Chile.

[23]  P. Hauser,et al.  Pneumocystis jiroveci Dihydropteroate Synthase Polymorphisms Confer Resistance to Sulfadoxine and Sulfanilamide in Saccharomyces cerevisiae , 2004, Antimicrobial Agents and Chemotherapy.

[24]  Ian G. Macreadie,et al.  Dihydropteroate Synthase Mutations in Pneumocystis jiroveci Can Affect Sulfamethoxazole Resistance in a Saccharomyces cerevisiae Model , 2004, Antimicrobial Agents and Chemotherapy.

[25]  E. Calderón,et al.  Pneumocystis jiroveci isolates with dihydropteroate synthase mutations in patients with chronic bronchitis , 2004, European Journal of Clinical Microbiology and Infectious Diseases.

[26]  C. Raccurt,et al.  Pneumocystis jiroveci Dihydropteroate Synthase Genotypes in Immunocompetent Infants and Immunosuppressed Adults, Amiens, France , 2004, Emerging infectious diseases.

[27]  A. Malin,et al.  Genotypes of Pneumocystis jiroveci Isolates Obtained in Harare, Zimbabwe, and London, United Kingdom , 2003, Antimicrobial Agents and Chemotherapy.

[28]  J. Kovacs,et al.  Genetic Analysis of Multiple Loci Suggests that Mutations in the Pneumocystis carinii f. sp.hominis Dihydropteroate Synthase Gene Arose Independently in Multiple Strains , 2001, Antimicrobial Agents and Chemotherapy.

[29]  C. Beard,et al.  Effect of mutations in Pneumocystis carinii dihydropteroate synthase gene on outcome of P carinii pneumonia in patients with HIV-1: a prospective study , 2001, The Lancet.

[30]  V. Luna,et al.  Amino Acid Repetitions in the Dihydropteroate Synthase of Streptococcus pneumoniae Lead to Sulfonamide Resistance with Limited Effects on SubstrateKm , 2001, Antimicrobial Agents and Chemotherapy.

[31]  C. Beard,et al.  Sulfa or sulfone prophylaxis and geographic region predict mutations in the Pneumocystis carinii dihydropteroate synthase gene. , 2000, The Journal of infectious diseases.

[32]  S. Meshnick,et al.  Pneumocystis carinii mutations are associated with duration of sulfa or sulfone prophylaxis exposure in AIDS patients. , 2000, The Journal of infectious diseases.

[33]  C. Beard,et al.  Genetic variation in Pneumocystis carinii isolates from different geographic regions: implications for transmission. , 2000, Emerging infectious diseases.

[34]  J. Lundgren,et al.  Effects of mutations in Pneumocystis carinii dihydropteroate synthase gene on outcome of AIDS-associated P carinii pneumonia , 1999, The Lancet.

[35]  J. E. Hyde,et al.  Sequence variation of the hydroxymethyldihydropterin pyrophosphokinase: dihydropteroate synthase gene in lines of the human malaria parasite, Plasmodium falciparum, with differing resistance to sulfadoxine. , 1994, European journal of biochemistry.

[36]  R. Miller,et al.  Oropharyngeal samples for detection of Pneumocystis carinii by DNA amplification. , 1993, The Quarterly journal of medicine.

[37]  Angela Cabello M,et al.  [Community antibiotic consumption in Chile, 2000-2008]. , 2011, Revista chilena de infectologia : organo oficial de la Sociedad Chilena de Infectologia.

[38]  T. Beroíza,et al.  [Etiology of pneumonia in chilean HIV-infected adult patients]. , 2011, Revista chilena de infectologia : organo oficial de la Sociedad Chilena de Infectologia.

[39]  Laura Bahamondes M,et al.  [Pneumocystis jiroveci pneumonia characteristics in adults with AIDS with or without antiretroviral therapy]. , 2006, Revista chilena de infectologia : organo oficial de la Sociedad Chilena de Infectologia.

[40]  G. Echevarría,et al.  [Lung diseases among HIV infected patients admitted to the "Instituto Nacional del Torax" in Santiago, Chile]. , 2005, Revista medica de Chile.

[41]  J. Helweg-Larsen,et al.  Rapid detection of dihydropteroate polymorphism in AIDS-related Pneumocystis carinii pneumonia by restriction fragment length polymorphism. , 2000, Scandinavian journal of infectious diseases.