RESUMEN
Over several decades, the economic situation and consideration of patient quality of life have been responsible for increased outpatient treatment. It is in this context that outpatient antimicrobial treatment (OPAT) has rapidly developed. The availability of elastomeric infusion pumps has permitted prolonged or continuous antibiotic administration by dint of a mechanical device necessitating neither gravity nor a source of electricity. In numerous situations, its utilization optimizes administration of time-dependent antibiotics while freeing the patient from the constraints associated with infusion by gravity, volumetric pump or electrical syringe pump and, more often than not, limiting the number of nurse interventions to one or two a day. That much said, the installation of these pumps, which is not systematically justified, entails markedly increased OPAT costs and is liable to expose the patient to a risk of therapeutic failure or adverse effects due to the instability of the molecules utilized in a non-controlled environment, instability that necessitates close monitoring of their use. More precisely, a prescriber must take into consideration the stability parameters of each molecule (infusion duration, concentration following dilution, nature of the diluent and pump temperature). The objective of this work is to evaluate the different means of utilization of elastomeric infusion pumps in intravenous antibiotic administration outside of hospital. Following a review of the literature, we will present a tool for optimized antibiotic prescription, in a town setting by means of an infusion device.
Asunto(s)
Antibacterianos/administración & dosificación , Terapia de Infusión a Domicilio/normas , Bombas de Infusión/normas , Infusiones Parenterales/normas , Administración Intravenosa , Atención Ambulatoria/normas , Antibacterianos/economía , Elastómeros , Terapia de Infusión a Domicilio/economía , Humanos , Bombas de Infusión/economía , Infusiones Intravenosas/economía , Infusiones Intravenosas/normas , Infusiones Parenterales/economía , Pacientes Ambulatorios , Calidad de Vida , Factores de RiesgoRESUMEN
INTRODUCTION: Pseudochromhidrosis denotes the production of colourless sweat that acquires colour after coming into contact with exogenous factors such as dyes in clothing, chemicals or chromogenic microorganisms. PATIENTS AND METHODS: A 9-year-old girl presented with progressive brown pigmentation predominantly on the nose, forehead, perioral region and cheeks. It was easily removable by rubbing with a moist compress, leaving normal-coloured skin as well as brown pigment on the compress. The same pigmentation recurred within 2h. The patient was not using cosmetics. Bacteriological culture of samples taken by rubbing the skin in affected areas on the face was positive for commensal bacteria of the skin (Actinomyces viscosus, Staphylococcus epidermidis, Cutibacterium acnes and Streptococcus sanguinis). Antibiotic therapy achieved total resolution of symptoms. CONCLUSION: Bacteria constitute the most frequent aetiology of pseudochromhidrosis. Where such a cutaneous condition exists, even in the absence of positive bacteriological testing, antibiotic therapy would seem to be indicated as a therapeutic test. Biopsy does not appear to be essential as a first-line approach where a bacterial cause is suspected, but it may be proposed in the event of resistance to antibiotics.
Asunto(s)
Infecciones Bacterianas , Trastornos de la Pigmentación , Enfermedades de las Glándulas Sudoríparas , Niño , Femenino , Humanos , Propionibacterium acnes , Enfermedades de las Glándulas Sudoríparas/diagnóstico , SudoraciónAsunto(s)
Infecciones por Corynebacterium/diagnóstico , Corynebacterium/aislamiento & purificación , Sepsis/diagnóstico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Infecciones Urinarias/diagnóstico , Anciano , Enfermedades Transmisibles Emergentes/diagnóstico , Enfermedades Transmisibles Emergentes/microbiología , Infecciones por Corynebacterium/orina , Femenino , Humanos , Sepsis/microbiología , Sepsis/orina , Urinálisis/métodos , Vejiga Urinaria Neurogénica/diagnóstico , Vejiga Urinaria Neurogénica/microbiología , Infecciones Urinarias/complicaciones , Infecciones Urinarias/microbiologíaRESUMEN
The emergence of bacterial resistance and the lack of new antibiotics in the pipeline represent a public health priority. Maximizing the quality of antibiotic prescriptions is therefore of major importance in terms of adequate preparation and administration modalities. Adequate preparation prevents the inactivation of antibiotics and is a prerequisite to maximizing their efficacy (taking into account the pharmacokinetic/pharmacodynamic relationship) and to minimizing their toxicity. Many antibiotic guidelines address the choice of drugs and treatment duration but none of them exclusively address preparation and administration modalities. These guidelines are based on the available literature and offer essential data for a proper antibiotic preparation and administration by physicians and nurses. They may lead to a better efficacy and to a reduced antibiotic resistance. Such guidelines also contribute to a proper use of drugs and improve the interaction between inpatient and outpatient care for a better overall management of patients.
Asunto(s)
Antibacterianos/administración & dosificación , Atención Ambulatoria , Antibacterianos/farmacocinética , Composición de Medicamentos/métodos , Composición de Medicamentos/normas , Farmacorresistencia Microbiana , Estabilidad de Medicamentos , Francia , Humanos , Prescripción Inadecuada , Bombas de Infusión , Infusiones Intravenosas , Inyecciones , Polvos , Solubilidad , SolucionesRESUMEN
INTRODUCTION: Bare-metal stents are used to treat arterial stenotic lesions. Morbidity and mortality are less important compared with other techniques. Drug-eluting balloons are often used to treat stent stenosis. We reported the case of a bare-metal stent infection after drug-eluting balloon and a review on the subject. MATERIAL AND METHOD: Two weeks after percutaneous transluminal angioplasty with paclitaxel-eluting balloon and a bare-metal stent, our patient presented an infection of the stent. Diagnosis was based on the clinical presentation, positron emission tomography findings and isolation of Propionibacterium granulosum in repeated blood cultures. Adapted antibiotic therapy was given for three months with removal of the surgical bare-stent. Antibiotic therapy was interrupted after a second positron emission tomography. A literature search (PubMed and Cochrane) was performed on the subject. RESULTS: We found 49 cases of peripheral bare-metal stent infection including our patient. This is a rare but serious complication with a high morbidity (25% amputation rate) and mortality (30%). It seems to be underestimated. Treatment is based on surgical ablation of the bare-metal stent and intravenous antibiotics. The role of the paclitaxel-eluting balloon is not clearly established but some authors believe that it can produce a local immunosuppression. CONCLUSION: We report the first case of bare-metal stent infection after paclitaxel-eluting balloon. This complication is rare and difficult to diagnose. Manifestations are often limited to skin signs. Functional and vital prognosis is poor.
Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Infecciones por Bacterias Grampositivas/etiología , Paclitaxel/efectos adversos , Propionibacterium/aislamiento & purificación , Infecciones Relacionadas con Prótesis/etiología , Stents/efectos adversos , Anciano de 80 o más Años , Aleaciones , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Arteriosclerosis Obliterante/complicaciones , Arteriosclerosis Obliterante/cirugía , Bacteriemia/etiología , Bacteriemia/microbiología , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/terapia , Reestenosis Coronaria/terapia , Remoción de Dispositivos , Contaminación de Equipos , Femenino , Arteria Femoral/cirugía , Gentamicinas/uso terapéutico , Infecciones por Bacterias Grampositivas/diagnóstico por imagen , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Inmunosupresores/efectos adversos , Paclitaxel/administración & dosificación , Paclitaxel/uso terapéutico , Ácido Penicilánico/análogos & derivados , Ácido Penicilánico/uso terapéutico , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/cirugía , Propionibacterium/patogenicidad , Infecciones Relacionadas con Prótesis/diagnóstico por imagen , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/microbiología , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
OBJECTIVE: The emergence of extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae has resulted in the increase of carbapenem prescriptions. The objective of our study was to determine the appropriateness of carbapenem prescriptions from initiation to reassessment of treatment, between 2009 and 2011. PATIENTS AND METHOD: A questionnaire drafted by infectious diseases specialists (IDS) and microbiologists was used to collect clinical and microbiological data concerning carbapenem prescriptions in 2009 and 2011. An IDS then compared the results to assess carbapenem prescription compliance with our hospital's local recommendations. RESULTS: Seventy-one prescriptions were included in 2009 and 32 in 2011. The carbapenem treatment had been most frequently probabilistic to treat nosocomial infections. The microbiological data revealed that the number of multidrug-resistant (MDR) infections had increased between 2009 and 2011, especially infections involving ESBL-producing Enterobacteriaceae. At treatment reassessment, in 2009 and 2011, 15 (21%) and 12 (38%) carbapenem prescriptions were appropriate and continued. Overall, when comparing the 2 periods, prescriptions complied with local guidelines from initiation to reassessment of treatment without any statistically significant difference (68% in 2009 and 75% in 2011). CONCLUSION: Our study results showed that MDR infections had increased and especially infections due to ESBL-producing Enterobacteriaceae; this was consistent with epidemiological data. We also proved that most carbapenem prescriptions were compliant with recommendations. The increased mobile IDS interventions in medical and surgical departments helped reach this rate of compliance. Carbapenem stewardship may be promoted even in a difficult epidemiological context, especially with IDS interventions for the duration of treatment or at treatment reassessment.
Asunto(s)
Carbapenémicos/uso terapéutico , Prescripciones de Medicamentos/estadística & datos numéricos , Adhesión a Directriz/estadística & datos numéricos , Farmacorresistencia Bacteriana , Enterobacteriaceae/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
We reviewed 80 adult cases of measles seen in a Parisian hospital during the French 2010-2011 outbreak. Fifty per cent had at least one complication: pneumonia and hepatitis were the most frequent. Forty per cent of hospitalized cases did not have any complications, suggesting clinically poor tolerance of measles in adults. The outcome was always favourable. Subjects were younger, were more often French nationals and had a higher socio-economic status than the overall population. This report suggests that immunity resulting from natural disease in patients from an area where the disease is endemic is protective in the long term.
Asunto(s)
Brotes de Enfermedades , Sarampión/epidemiología , Adulto , Femenino , Hepatitis Viral Humana/epidemiología , Hepatitis Viral Humana/etiología , Hospitales de Enseñanza , Humanos , Masculino , Sarampión/complicaciones , Paris/epidemiología , Neumonía/epidemiología , Neumonía/etiología , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: We retrospectively studied daptomycin use during 2010 at the Bichat-Claude-Bernard teaching-hospital (Paris) to observe the evolution of daptomycin prescriptions. PATIENTS AND METHODS: Twenty-one patients were included and several parameters were documented: site of infection, bacterial species involved, reason for daptomycin use, dose and clinical outcome. RESULTS: Ninety-five percent of daptomycin prescritions were off-label and most did not comply with local guidelines. Fifteen of the 21 patients were cured (71%), including 9 patients of the 12 with off-label and off-local recommendation prescriptions (75%). Osteitis and Enterococcus spp endocarditis were the new indications. Daptomycin was increasingly used at higher doses: 52% of our patients were given doses above 6mg/kg. Staphylococcus spp. was the most frequent pathogen responsible for infection is our patients, followed by Enterococcus spp. CONCLUSION: Daptomycin use is likely to evolve because of its effectiveness in the treatment of osteitis, left-sided and Enterococcus spp. infective endocarditis. It is generally used at higher doses, which are well tolerated. However, therapeutic monitoring needs to be developed. The antibiotic commission of our hospital gave new recommendations for daptomycin use in 2011.
Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infección Hospitalaria/tratamiento farmacológico , Daptomicina/uso terapéutico , Hospitales de Enseñanza/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Infecciones Bacterianas/microbiología , Infección Hospitalaria/microbiología , Prescripciones de Medicamentos/estadística & datos numéricos , Farmacorresistencia Microbiana , Quimioterapia Combinada , Utilización de Medicamentos/estadística & datos numéricos , Endocarditis/tratamiento farmacológico , Femenino , Adhesión a Directriz , Humanos , Prescripción Inadecuada/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Osteítis/tratamiento farmacológico , Paris , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Paradoxical tuberculosis immune reconstitution inflammatory syndrome (TB-IRIS) frequently follows the initiation of antiretroviral therapy (ART) in patients with tuberculosis (TB) and human immunodeficiency virus (HIV) co-infection. Treatment recommendations are nearly exclusively based on expert opinion. OBJECTIVE: To assess the clinical outcomes of patients treated using various strategies for TB-IRIS. METHODS: In a retrospective analysis of patients treated in Paris hospitals from 1996 to 2008, we describe TB-IRIS outcome, frequency of relapses and CD4 cell count changes after 12 months of ART for the following strategies: no treatment, interrupted ART and use of steroids. RESULT: Among 34 patients, TB-IRIS outcome was favourable in 10/10 with no treatment, 11/13 with ART interruption, 3/3 with ART interruption and simultaneous use of steroids and 8/8 with steroids alone. Relapses were observed in both the ART interruption (6/13, 46%) and steroids (4/8, 50%) groups, but were less frequent in the no-treatment group (1/10, 10%). Steroids were prescribed in 61% of the patients and had no significant side effects; steroid use was associated with a trend towards a lower median CD4 cell count at 12 months of ART compared to the others (230 vs. 322 cells/mm(3)), despite no baseline differences. CONCLUSION: TB-IRIS outcome was favourable regardless of the therapeutic strategies employed. Although steroids were widely used and well-tolerated, an initial wait-and-see attitude in the case of non-severe IRIS remains an interesting strategy to be evaluated.
Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Antituberculosos/uso terapéutico , VIH , Síndrome Inflamatorio de Reconstitución Inmune/tratamiento farmacológico , Tuberculosis/complicaciones , Adulto , Recuento de Linfocito CD4 , Coinfección , Femenino , Estudios de Seguimiento , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Humanos , Síndrome Inflamatorio de Reconstitución Inmune/etiología , Síndrome Inflamatorio de Reconstitución Inmune/inmunología , Masculino , Estudios Retrospectivos , Factores de Riesgo , Tuberculosis/tratamiento farmacológico , Tuberculosis/inmunologíaRESUMEN
Systemic lupus erythematosus (SLE) remains of unknown origin. Herpes viridae infections seem to play a role in the pathogenesis of this disease. We report a 31-year-old man who presented an acute cytomegalovirus (CMV) infection with persistent fever and myopericarditis as the presenting manifestation of SLE. This case report emphasizes a difficult differential diagnosis between SLE and an acute CMV infection and suggests a possible role of this virus in the pathogenesis of SLE.
Asunto(s)
Infecciones por Citomegalovirus/complicaciones , Citomegalovirus , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/virología , Enfermedad Aguda , Adulto , Antimaláricos/uso terapéutico , Antirreumáticos/uso terapéutico , Citomegalovirus/aislamiento & purificación , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/diagnóstico , Infecciones por Citomegalovirus/tratamiento farmacológico , Diagnóstico Diferencial , Quimioterapia Combinada , Fiebre/virología , Glucocorticoides/uso terapéutico , Humanos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Masculino , Miocarditis/virología , Pericarditis/virología , Resultado del TratamientoRESUMEN
The case of a woman with native mitral valve endocarditis due to Haemophilus parainfluenzae (HPI) associated with a pelvic abscess and endometriosis is reported. Although HPI is an infrequent pathogen involved in endocarditis, association to a gynaecological infection has never been reported. Endometriosis could increase this risk.
Asunto(s)
Absceso/complicaciones , Endocarditis Bacteriana/complicaciones , Endometriosis/complicaciones , Enfermedades de los Genitales Femeninos/microbiología , Infecciones por Haemophilus/complicaciones , Haemophilus parainfluenzae , Absceso/diagnóstico , Absceso/microbiología , Adulto , Antibacterianos/uso terapéutico , Fondo de Saco Recto-Uterino , Endocarditis Bacteriana/tratamiento farmacológico , Endocarditis Bacteriana/microbiología , Enfermedades de las Trompas Uterinas/microbiología , Femenino , Infecciones por Haemophilus/tratamiento farmacológico , Humanos , Válvula Mitral/microbiología , Enfermedades del Ovario/microbiología , Enfermedades Peritoneales/microbiologíaAsunto(s)
Enfermedad de Crohn/complicaciones , Infecciones por Citomegalovirus/complicaciones , Linfohistiocitosis Hemofagocítica/complicaciones , Adulto , Infecciones por Citomegalovirus/diagnóstico , Femenino , Humanos , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/virología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
BACKGROUND: Whether pregnancy has an impact on the evolution of CD4 cell counts in women treated with highly potent antiretrovirals before conception remains largely unknown. METHODS: Among patients enrolled in the ANRS CO8 (APROCO/COPILOTE) cohort, we selected all women aged between 18 and 50 years at initiation of combination antiretroviral therapy (cART). Slopes of CD4 cell counts during follow-up were estimated using mixed longitudinal models with time-dependent indicators for pregnancy and delivery. RESULTS: Of the 260 selected HIV-infected women, a pregnancy occurred in 39 women in a median follow-up time of 66 months. Women who became pregnant had higher CD4 cell count at baseline but this difference progressively lessened during follow-up because they had a slower increase than women who did not become pregnant. The estimated slope of CD4 cell count decreased significantly from +2.3 cells/muL/month before pregnancy and in women who did not become pregnant to -0.04 cells/microL/month after delivery (P=0.0003). CONCLUSION: A significant increase in CD4 cell count may be preferable before pregnancy in women treated with cART, in order to overcome the evolution observed after pregnancy.
Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH/inmunología , VIH-1/inmunología , Síndrome Inflamatorio de Reconstitución Inmune/etiología , Complicaciones Infecciosas del Embarazo/inmunología , Adolescente , Adulto , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Atención Preconceptiva , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/virología , ARN Viral , Factores de Riesgo , Adulto JovenRESUMEN
OBJECTIVE: The characteristics of patients with a suspected SARS hospitalized in a Paris hospital were studied to analyze the hypothetic differences between epidemiologic and clinical teams in the management of an epidemic emerging disease, and to gather experience for the management of the next outbreak. STUDY DESIGN: All 90 patients hospitalized between March 16 and April 30, 2003, were included. Epidemiological and clinical data were shared with the French National Institute for Health. Cases were classified according to both the official definition ("possible", "probable", "excluded") and a local one, adapted from the official definition but including an additional level of suspicion ("equivocal"), intermediate between "possible" and "excluded". RESULTS: The initial assessment was different in 39% of the cases (n=35), according to epidemiological (n=24) or clinical (n=11) elements. The final assessment diverged in 54% of the cases (n=47). All patients were officially considered as "excluded" for epidemiologists, while 47 remained as "possible" or "equivocal" cases of SARS according to the clinicians. CONCLUSION: The risk assessment was different in almost 40% of the cases, with no impact on epidemic diffusion or hospital-borne exposure as no probable case of SARS was diagnosed among these patients or their households. The confrontation of these different but complementary points of view will thus enrich the interdisciplinary management of eventual future outbreaks.
Asunto(s)
Síndrome Respiratorio Agudo Grave/diagnóstico , Síndrome Respiratorio Agudo Grave/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Medición de RiesgoAsunto(s)
Arterias Cerebrales/patología , Hemorragia Cerebral/patología , Endocarditis/complicaciones , Aneurisma Intracraneal/complicaciones , Microcirculación/patología , Adulto , Antibacterianos/uso terapéutico , Arterias Cerebrales/microbiología , Arterias Cerebrales/fisiopatología , Hemorragia Cerebral/microbiología , Hemorragia Cerebral/fisiopatología , Diagnóstico Diferencial , Progresión de la Enfermedad , Endocarditis/microbiología , Humanos , Aneurisma Intracraneal/fisiopatología , Imagen por Resonancia Magnética , Masculino , Microcirculación/microbiología , Microcirculación/fisiopatología , Valor Predictivo de las PruebasRESUMEN
Various emerging diseases have been reported in recent years as epidemiologic monitoring improves. These infections can compromise the pregnancy, through adverse maternal outcomes, as well as the outcome for the child following transmission. We report a review of the literature concerning the most quoted emergent virus (H5N1, SARS Coronavirus, Chikungunya, West Nile virus), and relate the perinatal management.
Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Transmisión Vertical de Enfermedad Infecciosa , Complicaciones Infecciosas del Embarazo/epidemiología , Resultado del Embarazo , Virosis/epidemiología , Infecciones por Alphavirus/epidemiología , Infecciones por Alphavirus/transmisión , Virus Chikungunya , Enfermedades Transmisibles Emergentes/transmisión , Femenino , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Subtipo H5N1 del Virus de la Influenza A , Gripe Humana/epidemiología , Gripe Humana/transmisión , Embarazo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Síndrome Respiratorio Agudo Grave/epidemiología , Síndrome Respiratorio Agudo Grave/transmisión , Virosis/transmisión , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/transmisión , Virus del Nilo OccidentalRESUMEN
To reduce the number of daily pills for improving adherence to antiretrovirals, 17 protease inhibitor-treated patients receiving toxoplasmic encephalitis (TE) standard maintenance therapy were instead given cotrimoxazole 960 mg twice daily. After a median follow-up of 31 months, one relapsed after three months, TE relapse incidence = 2.1 cases per 100 patient-years (95% confidence interval, 0.05-11.3). This strategy could be useful for patients awaiting immune reconstitution which allows the interruption of TE maintenance therapy.
Asunto(s)
Antiinfecciosos/uso terapéutico , Infecciones por VIH/parasitología , Toxoplasma , Toxoplasmosis Cerebral/prevención & control , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Animales , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Femenino , Estudios de Seguimiento , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , Humanos , Masculino , Recurrencia , Toxoplasmosis Cerebral/virología , Carga ViralRESUMEN
Whereas valacyclovir is widely used and is recommended by some authors in moderately immunocompromised HIV-infected patients, its use has not been validated by clinical studies. We report a case of herpes zoster in an HIV-infected patient for whom neurologic complication was not avoided despite valacyclovir therapy. Clinical outcome was favorable after intravenous acyclovir. This case suggests careful monitoring of valacyclovir in HIV-infected patients is necessary.