Identificación molecular de especies de candida en pacientes quemados
Medical histories of 36 burned patients with documented fungal infection,\nadmitted to the Intensive Care Unit of the Hospital Municipal de Quemados del Gobierno\nde la Ciudad de Buenos Aires between January 2011 and December 2014, were analyzed.\nA total of 52 species of Candida were identified by...
Guardado en:
| Autor principal: | |
|---|---|
| Otros Autores: | |
| Formato: | Tesis de maestría acceptedVersion |
| Lenguaje: | Español |
| Publicado: |
Facultad de Farmacia y Bioquímica
2017
|
| Materias: | |
| Acceso en línea: | http://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=afamaster&cl=CL1&d=HWA_1901 http://repositoriouba.sisbi.uba.ar/gsdl/collect/afamaster/index/assoc/HWA_1901.dir/1901.PDF |
| Aporte de: |
| Sumario: | Medical histories of 36 burned patients with documented fungal infection,\nadmitted to the Intensive Care Unit of the Hospital Municipal de Quemados del Gobierno\nde la Ciudad de Buenos Aires between January 2011 and December 2014, were analyzed.\nA total of 52 species of Candida were identified by conventional and molecular methods\nfrom the culture collection stored at -20 ºC at the Laboratory of Hospital de Quemados in\nthe patients studied. The mean hospitalization period was 46.7 days, ranging from 9 to\n218 days. They belonged to females 63.9% (n = 23) and 36.1% male (n = 13). The burned\nbody surface area was estimated at 31-50% in 33.3% of the patients (p=0.03). This\npercentage was observed among the higher age group (59 years of age). Instead, patients\nin the group with a mean age of 19 years suffered burns affecting 71% - 100% of their\nbody surface area. With regard to burn depth, fourth-degree burns affected 69.4% of the\npatients, which indicates the seriousness of the injuries in the patients studied. A total of\n75% of the patients showed burns in different locations (torso, face, lower and upper\nlimbs) and only 25% showed injuries only on the lower limbs, upper limbs or torso. The\ncausative agents of burns were: combustible substances (alcohol, gasoline, explosion):\n41.7%, direct fire: 25%, heaters: 13.9%, water: 16.7% and lastly, electricity: 2.8%. It is\nremarkable that in those cases in which the burn causative agent was a combustible\nsubstance, alcohol was the prevalent agent. When studying causative agents in relation to\nage, burn injuries by fire or heaters were found mainly older patients. Conversely, burns\ncaused by alcohol, combustible substances and electricity were reported on younger\npatients. When studying causative agents in relation to sex, alcohol was found to be the\nprevalent element in females. This higher rate for women is associated with the fact that the causative agents of the burn injury are alcohol and direct fire, according to medical\nhistory including injuries by a close third party. They are the current causes of the\nfemicides reported in our country in women under 40 years of age. Electrical burns and\ngasoline burn injuries were affected males exclusively.When analyzing the correlation\nbetween the burned surface area and the cause (combustible substances vs. other agents),\nit was found that causes other than combustible substances generate smaller burn injuries\n(p= 0.01). However, second-degree burns were observed when the agent was a\ncombustible substance (alcohol, gasoline or explosion) (p=0.03), as a result of a deeper\nburn.Fifty per cent of the burned patients showed inhalation injuries (SII), with both\ncombustible substances and fire as causative agents of the burn injury. A central line was\nrequired in 88.9% of the burned patients. Femoral lines were used in 90.6% and upper\nlines (subclavian and/or jugular lines), in 9.4%. The mean number of lines used per\npatient was 5.8. Orotracheal intubation and tracheostomy were performed in 72.2% and\n41.7% of the patients, respectively. A total of 91.7 % of the patients underwent surgical\ntreatment (escharectomy: 100%, escharotomy: 42.4%, fasciotomy: 54.5% and limb\namputation: 6.1%) while 8.3% of the patients did not undergo any surgical treatment\n(only wound lavage). Following surgical treatment and, after reaching viable tissue, the\nwound was covered with skin grafts. Autograft was performed in 97.2% of the patients,\nshowing firm adherence to the underlying tissue in 75% of the cases. In twenty-five per\ncent of the unsuccessful cases, the mortality rate was 100% (p< 0.01), the main cause\nbeing the septic shock. Inotropes were required in 72.2% of the cases and anti-fungal\ndrugs in 91.7%. A total of 58.8% were initially treated with Fluconazole. The rest of the\ncases were treated with Amphotericin B Liposomal. Death occurred in 38.8% of the patients, its rate being higher among patients over 65 years of age (p= 0.018), on\ninotropes (noradrenaline) (p < 0.001), those patients suffering inhalation injury (p= 0.04),\nthose who had undergone fasciotomy (p=0.04) and those with a history or in a high-risk\ngroup (p = 0.002). Infection by bacteria occurred in 100% of the burned patients, the\nmicroorganisms being: Gram-negative bacteria such as multiresistant Acinetobacter\nbaumannii, Pseudomonas aeruginosa and carbapenemase-producing (KPC) Klebsiella\npneumoniae. Among Gram-positive bacteria, the most prevalent was methicillin-resistant\nS. Aureus (MRSA). The mean time of the onset of bacterial infections was 4 days\nfollowing admission to the Intensive Care Unit. A total of 38.9% of the patients had an\nAPACHE II score of 31-40 while 8.3% had a score of 41-46. A total of 77.7% showed a\nCandida score of 3.Fungal infections are a major cause of morbi-mortality in burned\npatients since they are ideal hosts for opportunistic infections. The incidence of fungal\ninfection was 39.3 for every 1,000 burned patients. On average, the cases of Candidiasis\noccurred after 21.4 days of the admission to the intensive care unit (1-3 weeks).The most\nfrequently isolated yeast was C. albicans in all samples analyzed (wound biopsy samples,\nurocultures, blood cultures, tracheal aspirate cultures, catheter tip cultures). Thus, C.\nalbicans amounted to 53.8%, C. tropicalis to 23.1%, C. parapsilosis sensu stricto\nto13.5%, C. krusei to 5.8%, C. glabrata and C krusei to 1.9 % each. C. albicans was the\nprevalent species in blood cultures, followed by C. parapsilosis. In the urocultures, nonalbicans\nCandida species surpassed C. albicans. Patients with positive blood cultures for\ncandidaemias showed higher mortality than those with negative blood cultures for\ncandidaemias, with no statistically significant difference (p= 0.091). Molecular\nidentification (HWP1 gene amplification by PCR) and microbiological identification agreed with C. albicans and C. dubliniensis. For some C. albicans isolates, the\namplification produced two fragments of DNA. The smaller fragment (941 bp) was\nproduced by the HWP1 gene and the larger fragment resulted from the RBT1 gene partial\namplification by a non-specific primer binding but the identification of C. albicans was\nconfirmed by clone sequencing. Molecular identification of isolates was required for the\nidentification of C. parapsilosis and C. glabrata as C. parapsilosis sensu stricto and C.\nglabrata species complex. For C. glabrata species complex, PCR reaction for RLP31\ngene, which codes for a 60S ribosomal protein, determined the absence of C. bracarensis\nand C. nivariensis, and the presence of C. glabrata. Molecular identification of C.\nparapsilosis species complex by specific primers for each of these complex species by\nsequencing of ITS1 and ITS2 regions of rDNA enabled the identification of C.\nparasilopsis sensu stricto. C. orthosilopsis and C. metapsilosis were not detected |
|---|