A proposed cleaning classification system for reusable medical devices to complement the Spaulding classification

A central tenet in infection prevention is application of the Spaulding classification system for the safe use of medical devices. Initially defined in the 1950s, this system defines devices and surfaces as being critical, semi-critical or non-critical depending on how they will be used on a patient. Different levels of antimicrobial treatment, defined as various levels of disinfection or sterilization, are deemed appropriate to reduce patient risk of infection. However, a focus on microbial inactivation is insufficient to address this concern, which has been particularly highlighted in routine healthcare facility practices, emphasizing the underappreciated importance of cleaning and achieving acceptable levels of cleanliness. A deeper understanding of microbiology has evolved since the 1950s, which has led to re-evaluation of the Spaulding classification along with a commensurate emphasis on achieving appropriate cleaning. Albeit underappreciated, cleaning has always been important as the presence of residual materials on surfaces can interfere with the efficacy of the antimicrobial process to inactivate micro-organisms, as well as other risks to patients including device damage, malfunction and biocompatibility concerns. Unfortunately, this continues to be relevant, as attested by reports in the literature on the occurrence of device-related infections and outbreaks due to failures in processing expectations. This reflects, in part, increasing sophistication in device features and reuse, along with commensurate manufacturer's instructions for use. Consequently, this constitutes the first description and recommendation of a new cleaning classification system to complement use of the traditional Spaulding definitions to help address these modern-day technical and patient risk challenges. This quantitative risk-based classification system highlights the challenge of efficient cleaning based on the complexity of device features present, as an isolated variable impacting cleaning. This cleaning classification can be used in combination with the Spaulding classification to improve communication of cleaning risk of a reusable medical device between manufacturers and healthcare facilities, and improve established cleaning practices. This new cleaning classification system will also inform future creation, design thinking and commensurate innovations for the sustainable safe reuse of important medical devices.

A review of Spaulding's classification system for effective cleaning, disinfection and sterilization of reusable medical devices: Viewed through a modern-day lens that will inform and enable future sustainability

Despite advances in medicine and innovations in many underpinning fields including disease prevention and control, the Spaulding classification system, originally proposed in 1957, remains widely used for defining the disinfection and sterilization of contaminated re-usable medical devices and surgical instruments. Screening PubMed and Scopus databases using a PRISMA guiding framework generated 272 relevant publications that were used in this review. Findings revealed that there is a need to evolve how medical devices are designed, and processed by cleaning, disinfection (and/or sterilization) to mitigate patient risks, including acquiring an infection. This Spaulding Classification remains in use as it is logical, easily applied and understood by users (microbiologists, epidemiologists, manufacturers, industry) and by regulators. However, substantial changes have occurred over the past 65 years that challenge interpretation and application of this system that includes inter alia emergence of new pathogens (viruses, mycobacteria, protozoa, fungi), a greater understanding of innate and adaptive microbial tolerance to disinfection, toxicity risks, increased number of vulnerable patients and associated patient procedures, and greater complexity in design and use of medical devices. Common cited examples include endoscopes that enable non- or minimal invasive procedures but are highly sophisticated with various types of materials (polymers, electronic components etc), long narrow channels, right angle and heat-sensitive components and various accessories (e.g., values) that can be contaminated with high levels of microbial bioburden and patient tissues after use. Contaminated flexible duodenoscopes have been a source of several significant infection outbreaks, where at least 9 reported cases were caused by multidrug resistant organisms [MDROs] with no obvious breach in processing detected. Despite this, there is evidence of the lack of attention to cleaning and maintenance of these devices and associated equipment. Over the last few decades there is increasing genomic evidence of innate and adaptive resistance to chemical disinfectant methods along with adaptive tolerance to environmental stresses. To reduce these risks, it has been proposed to elevate classification of higher-risk flexible endoscopes (such as duodenoscopes) from semi-critical [contact with mucous membrane and intact skin] to critical use [contact with sterile tissue and blood] that entails a transition to using low-temperature sterilization modalities instead of routinely using high-level disinfection; thus, increasing the margin of safety for endoscope processing. This timely review addresses important issues surrounding use of the Spaulding classification system to meet modern-day needs. It specifically addresses the need for automated, robust cleaning and drying methods combined with using real-time monitoring of device processing. There is a need to understand entire end-to-end processing of devices instead of adopting silo approaches that in the future will be informed by artificial intelligence and deep-learning/machine learning. For example, combinational solutions that address the formation of complex biofilms that harbour pathogenic and opportunistic microorganisms on the surfaces of processed devices. Emerging trends are addressed including future sustainability for the medical devices sector that can be enabled via a new Quintuple Helix Hub approach that combines academia, industry, healthcare, regulators, and society to unlock real world solutions.

COVID-19 in Multiple Sclerosis: Clinically reported outcomes from the UK Multiple Sclerosis Register

BACKGROUND

In March 2020, the United Kingdom Multiple Sclerosis Register (UKMSR) established an electronic case return form, designed collaboratively by MS neurologists, to record data about COVID-19 infections in people with MS (pwMS).

OBJECTIVES

Examine how hospital admission and mortality are affected by disability, age and disease modifying treatments (DMTs) in people with Multiple Sclerosis with COVID-19.

METHODS

Anonymised data were submitted by clinical teams. Regression models were tested for predictors of hospitalisation and mortality outcomes. Separate analyzes compared the first and second 'waves' of the pandemic.

RESULTS

Univariable analysis found hospitalisation and mortality were associated with increasing age, male gender, comorbidities, severe disability, and progressive MS; severe disability showed the highest magnitude of association. Being on a DMT was associated with a small, lower risk. Multivariable analysis found only age and male gender were significant. Post hoc analysis demonstrated that factors were significant for hospitalisation but not mortality. In the second wave, hospitalisation and mortality were lower. Separate models of the first and second wave using age and gender found they had a more important role in the second wave.

CONCLUSIONS

Features associated with poor outcome in COVID-19 are similar to other populations and being on a DMT was not found to be associated with adverse outcomes, consistent with smaller studies. Once in hospital, no factors were predictive of mortality. Reassuringly, mortality appears lower in the second wave.

Simulation modelling as a tool for knowledge mobilisation in health policy settings: a case study protocol

BACKGROUND

Evidence-informed decision-making is essential to ensure that health programs and services are effective and offer value for money; however, barriers to the use of evidence persist. Emerging systems science approaches and advances in technology are providing new methods and tools to facilitate evidence-based decision-making. Simulation modelling offers a unique tool for synthesising and leveraging existing evidence, data and expert local knowledge to examine, in a robust, low risk and low cost way, the likely impact of alternative policy and service provision scenarios. This case study will evaluate participatory simulation modelling to inform the prevention and management of gestational diabetes mellitus (GDM). The risks associated with GDM are well recognised; however, debate remains regarding diagnostic thresholds and whether screening and treatment to reduce maternal glucose levels reduce the associated risks. A diagnosis of GDM may provide a leverage point for multidisciplinary lifestyle modification interventions. This research will apply and evaluate a simulation modelling approach to understand the complex interrelation of factors that drive GDM rates, test options for screening and interventions, and optimise the use of evidence to inform policy and program decision-making.

METHODS/DESIGN

The study design will use mixed methods to achieve the objectives. Policy, clinical practice and research experts will work collaboratively to develop, test and validate a simulation model of GDM in the Australian Capital Territory (ACT). The model will be applied to support evidence-informed policy dialogues with diverse stakeholders for the management of GDM in the ACT. Qualitative methods will be used to evaluate simulation modelling as an evidence synthesis tool to support evidence-based decision-making. Interviews and analysis of workshop recordings will focus on the participants' engagement in the modelling process; perceived value of the participatory process, perceived commitment, influence and confidence of stakeholders in implementing policy and program decisions identified in the modelling process; and the impact of the process in terms of policy and program change.

DISCUSSION

The study will generate empirical evidence on the feasibility and potential value of simulation modelling to support knowledge mobilisation and consensus building in health settings.

Cleaning, disinfection and sterilization of surface prion contamination

BACKGROUND

Prion contamination is a risk during device reprocessing, being difficult to remove and inactivate. Little is known of the combined effects of cleaning, disinfection and sterilization during a typical reprocessing cycle in clinical practice.

AIM

To investigate the combination of cleaning, disinfection and/or sterilization on reducing the risk of surface prion contamination.

METHODS

In vivo test methods were used to study the impact of cleaning alone and cleaning combined with thermal disinfection and high- or low-temperature sterilization processes. A standardized test method, based on contamination of stainless steel wires with high titres of scrapie-infected brain homogenates, was used to determine infectivity reduction.

FINDINGS

Traditional chemical methods of surface decontamination against prions were confirmed to be effective, but extended steam sterilization was more variable. Steam sterilization alone reduced the risk of prion contamination under normal or extended exposure conditions, but did show significant variation. Thermal disinfection had no impact in these studies. Cleaning with certain defined formulations in combination with steam sterilization can be an effective prion decontamination process, in particular with alkaline formulations. Low-temperature, gaseous hydrogen peroxide sterilization was also confirmed to reduce infectivity in the presence and absence of cleaning.

CONCLUSION

Prion decontamination is affected by the full reprocessing cycle used on contaminated surfaces. The correct use of defined cleaning, disinfection and sterilization methods as tested in this report in the scrapie infectivity assay can provide a standard precaution against prion contamination.

Bacterial spore structures and their protective role in biocide resistance

The structure and chemical composition of bacterial spores differ considerably from those of vegetative cells. These differences largely account for the unique resistance properties of the spore to environmental stresses, including disinfectants and sterilants, resulting in the emergence of spore-forming bacteria such as Clostridium difficile as major hospital pathogens. Although there has been considerable work investigating the mechanisms of action of many sporicidal biocides against Bacillus subtilis spores, there is far less information available for other species and particularly for various Clostridia. This paucity of information represents a major gap in our knowledge given the importance of Clostridia as human pathogens. This review considers the main spore structures, highlighting their relevance to spore resistance properties and detailing their chemical composition, with a particular emphasis on the differences between various spore formers. Such information will be vital for the rational design and development of novel sporicidal chemistries with enhanced activity in the future.

Resistance and cross-resistance to oxidising agents of bacterial isolates from endoscope washer disinfectors

Bacteria isolated from washer disinfectors using chlorine dioxide as a high-level disinfectant were exposed to peracetic acid, chlorine dioxide and hydrogen peroxide to investigate their susceptibility and possible bacterial cross-resistance to these highly reactive oxidising biocides. A standard suspension test was used to establish a rate of kill of these biocides against two stable isolates (Bacillus subtilis and Micrococcus luteus). Suspension tests demonstrated that 'in use' concentrations were not always effective to provide the required disinfection efficacy within recommended exposure times and in some instances a 60min exposure was necessary to achieve a reduction in number by a factor of 10(5). It appears that vegetative Gram-positive isolates can become resistant to oxidising agents in vitro, and that cross-resistance to related compounds can occur. Since these bacteria are deemed to be susceptible to highly reactive biocides, there should be further study of the resistance mechanisms in these isolates to explain their survival.

Relationship between mycobacteria and amoebae: ecological and epidemiological concerns

Since the discovery that Legionella pneumophila can survive and grow within free-living amoebae, there has been an increasing number of microbial species shown to have similar relationships. These include many bacterial species, fungi, other protozoa (e.g. Cryptosporidium) and viruses. Among bacteria, mycobacteria are of particular importance because of their role in human and animal infections. This review will consider the progress made in understanding the relationships between mycobacteria and amoebae, and their consequences in terms of ecology and epidemiology.

The Centre for Health Informatics at the University of New South Wales - a Clinical Informatics Research Centre

Building a sustainable health system in the 21st Century will require the reinvention of much of the present day system, and the intelligent use of information and communication technologies (ICT) to deliver high quality, safe, efficient and affordable health care. The Centre for Health Informatics (CHI) is Australia’s largest academic research group in this emerging discipline.

Our research is underpinned by a planning process, based on different future scenarios for the health system, which helps us identify longer-term problems needing a sustained research effort. A research competency matrix is used to ensure that the Centre has the requisite core capabilities in the research methods and tools needed to pursue our research program.

The Centre’s work is internationally recognized for its contributions in the development of intelligent search systems to support evidence-based healthcare, developing evaluation methodologies for ICT, and in understanding how communication shapes the safety and quality of health care delivery. Centre researchers also are working on safety models and standards for ICT in healthcare, mining complex gene micro array, medical literature and medical record data, building health system simulation methods to model the impact of health policy changes, and developing novel computational methods to automate the diagnosis of 3-D medical images.

Any individual research group like CHI must necessarily focus on a few areas to allow it to develop sufficient research capacity to make novel and internationally significant contributions. As CHI approaches the end of its first decade, it is becoming clear that developing capacity becomes increasingly challenging as the research territory changes under our feet, and that the Centre will continue to evolve and shift its focus in the years to come.

The Centre for Health Informatics at the University of New South Wales--a clinical informatics research centre

OBJECTIVES

Building a sustainable health system in the 21st Century will require the reinvention of much of the present day system, and the intelligent use of information and communication technologies (ICT) to deliver high quality, safe, efficient and affordable health care. The Centre for Health Informatics (CHI) is Australia's largest academic research group in this emerging discipline.

METHODS

Our research is underpinned by a planning process, based on different future scenarios for the health system, which helps us identify longer-term problems needing a sustained research effort. A research competency matrix is used to ensure that the Centre has the requisite core capabilities in the research methods and tools needed to pursue our research program.

RESULTS

The Centre's work is internationally recognized for its contributions in the development of intelligent search systems to support evidence-based healthcare, developing evaluation methodologies for ICT, and in understanding how communication shapes the safety and quality of health care delivery. Centre researchers also are working on safety models and standards for ICT in healthcare, mining complex gene micro array, medical literature and medical record data, building health system simulation methods to model the impact of health policy changes, and developing novel computational methods to automate the diagnosis of 3-D medical images.

CONCLUSIONS

Any individual research group like CHI must necessarily focus on a few areas to allow it to develop sufficient research capacity to make novel and internationally significant contributions. As CHI approaches the end of its first decade, it is becoming clear that developing capacity becomes increasingly challenging as the research territory changes under our feet, and that the Centre will continue to evolve and shift its focus in the years to come.

Polymorphisms in the interleukin-4 and IL-4 receptor genes and multiple sclerosis: a study in Spanish-Basque, Northern Irish and Belgian populations

Cytokine gene polymorphisms are known to influence susceptibility and disease course of many autoimmune diseases. Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system white matter characterized by inflammation, demyelination and axonal damage. We analysed both the well-known intronic variable number of tandem repeat (VNTR) and +33 C/T single-nucleotide polymorphisms (SNP) in the IL-4 gene, as well as the functional Q551R SNP in the IL4-R gene in a cohort of three distinct populations comprising sporadic cases and controls from the northern Spanish Basque Country and Northern Ireland, as well as family trios from Belgium. The IL-4 +33 TT genotype was decreased in primary progressive (PP) versus relapsing-remitting (RR) patients in the Northern Irish population (OR = 0.14; 95% CI = 0.018-1.09). Two-marker haplotype distribution of the VNTR and +33 C/T SNP in PP patients differed from that seen in RR patients in Northern Ireland (P = 0.03). The R allele of the Q551R SNP was significantly under-transmitted in the Belgian trio families (P = 0.003), although this effect was not seen in the Northern Irish and Basque data sets. We did not identify IL-4-IL4-R gene-gene interaction in determining susceptibility or clinical parameters of MS. Disease or genetic heterogeneity or both may be responsible for the observed lack of reproduction in different populations. Our data reinforce recent findings for a role of IL4-R in susceptibility to MS.

Decontamination with vaporized hydrogen peroxide is effective against Mycobacterium tuberculosis

AIMS

To determine the efficacy of room fumigation with vaporized hydrogen peroxide (VHP) in decontamination of viable Mycobacterium tuberculosis.

METHODS AND RESULTS

About 8 x 10(4)-2.3 x 10(6) CFU of M. tuberculosis H37Rv and M. tuberculosis Beijing were dried in 10-microl drops in tissue culture plates, placed in steam-permeable Tyvek pouches and distributed on laboratory surfaces. The room was exposed to VHP delivered by air conditioning. Different exposure conditions were tested. Exposure to VHP resulted in sterilization of the bacterial samples in three different test runs.

CONCLUSIONS

VHP treatment is an effective means of reducing and eliminating room contaminations of M. tuberculosis.

SIGNIFICANCE AND IMPACT OF THE STUDY

Fumigation with VHP represents an alternative to formaldehyde fumigation, particularly for decontamination of animal rooms in tuberculosis research laboratories.

Haplotype analysis of the preprotachykinin-1 (TAC1) gene in multiple sclerosis

The potential relevance of chromosome 7q21-22 in susceptibility to multiple sclerosis (MS) has been highlighted in genome-wide linkage screens as well as in association studies of 7q-specific polymorphic microsatellites. Especially, recent, independently performed studies have provided evidence for significant association of the markers D7S554 and D7S3126 with MS in Sardinian, Northern Irish and Spanish-American cohorts. The gene most closely located to these markers is the neuropeptide preprotachykinin-1 (TAC1) gene. Both its position and the array of biological functions exerted by its expression products make it a logical primary choice for further scrutiny as the putative chromosome 7q21-22 MS susceptibility gene. We report identification of eight polymorphisms in this gene by means of a sequencing approach. A Northern Irish case-control was typed for six of these polymorphisms. One of these, an intron 1 single-nucleotide polymorphism (SNP), showed significant association with MS (P=0.009). Two-marker haplotypes composed of allelic combinations of TAC1 promoter-intron 1 SNPs were highly significantly associated with MS and more so with the relapsing-remitting form of this disease. While independent reproduction of these data in other data sets is indicated, our work is suggestive for a role of the TAC1 gene in MS. Genes and Immunity (2005) 6, 265-270. doi:10.1038/sj.gene.6364175 Published online 24 February 2005.

Biodecontamination of animal rooms and heat-sensitive equipment with vaporized hydrogen peroxide

Common methods used to decontaminate and disinfect laboratory animal areas are difficult to standardize, labor-intensive, and potentially hazardous for staff members and the environment. As an alternative to traditional methods, we tested fumigation with vaporized hydrogen peroxide by using the VHP 1000 Biodecontamination System. The design of our air-conditioning system allowed the connection of the generator to any animal room by using the ventilation piping, thus forming a closed circuit. A 3-h cycle consisting of dehumidification, conditioning, sterilization, and aeration was developed and shown to be effective. The biodecontamination process was monitored during five independent trials using chemical and biological (Bacillus stearothermophilus spores) indicators. Contact plates for testing surfaces and room air for environmental bacteria, yeasts, and fungi consistently showed fewer than 10 colony-forming units per 100 cm2 or per 1 liter air. In addition, this method proved successful with heat-sensitive equipment like the blower units of individually ventilated caging systems. Overall, the system was easy to use and very effective in biodecontaminating animal rooms and equipment in a reproducible manner. There were no signs of corrosion or functional damage after more than 10 fumigation cycles. Work load and potential health risk for staff members and the environment was negligible.

Use of Dacron as an alternative carrier for evaluating oxidizing sterilants in the AOAC sporicidal test

The AOAC sporicidal method (966.04) recommends the use of porcelain penicylinders and black waxed silk sutures as carriers for demonstrating the sporicidal activity of sterilants. However, the silk carriers are not suitable for evaluating the sporicidal efficacy of oxidizing agents, and an inert polyester material (Dacron) is recommended as an alternative. Dacron provides an equivalent microbial and physical challenge to silk. Microbiologically, both materials demonstrated similar HCI resistance, which is required by the AOAC test, as well as equivalent spore loading and spore wash-off. Electron microscopy showed that both materials present the same braided microstructure, providing an equivalent physical challenge to the test sterilant. Dacron was more consistent than silk, and did not require extraction prior to spore loading. The extraction method for black waxed silk was variable and incomplete, which may compromise the activity of oxidizing sterilants and add to method variability. Silk was also structurally altered in the presence of oxidizing sterilants and increased sterilant degradation. Dacron did not affect the sterilant and was inert in the presence of oxidizing agents. Dacron sutures are proposed as inert alternatives to silk for evaluating the sporicidal efficacy of oxidizing agents.

Interaction of disinfectant residues on cleanroom substrates

This study will determine the levels of disinfectant residues on stainless steel surfaces after simulated manual cleaning activities. Additionally, this study will determine if chemical interactions between different chemical agents, representative of commonly used cleanroom disinfectant technologies, subsequently applied to the same surfaces exist, and to what degree these interactions impact sporicidal performance of an oxidizing biocide against Bacillus subtilis.

Clinical correlation of a skin antisepsis model

The use of pigskin as a test substrate for evaluating topical antimicrobial activity has been developed. Simulated handwashing protocols with this in vitro model in parallel with in vivo studies have been evaluated, based on an ASTM method for the clinical evaluation of a healthcare personnel handwash. Using Serratia marcescens as the test organism, similar log reductions were observed using the in vitro model when compared to in vivo efficacy. Results suggest that this model can be used as a reliable indicator of antiseptic efficacy on the skin. The use of sterilized skin simplifies the use of this model for both efficacy and skin-pathogen interaction studies.

Antiseptics and disinfectants: activity, action, and resistance

Antiseptics and disinfectants are extensively used in hospitals and other health care settings for a variety of topical and hard-surface applications. A wide variety of active chemical agents (biocides) are found in these products, many of which have been used for hundreds of years, including alcohols, phenols, iodine, and chlorine. Most of these active agents demonstrate broad-spectrum antimicrobial activity; however, little is known about the mode of action of these agents in comparison to antibiotics. This review considers what is known about the mode of action and spectrum of activity of antiseptics and disinfectants. The widespread use of these products has prompted some speculation on the development of microbial resistance, in particular whether antibiotic resistance is induced by antiseptics or disinfectants. Known mechanisms of microbial resistance (both intrinsic and acquired) to biocides are reviewed, with emphasis on the clinical implications of these reports.

Behavioural response home monitoring of good and insomniac sleepers

Can the fundamental differences in sleep structure known to differentiate good from insomniac sleepers (e.g., sleep length, sleep onset latency [SOL], number of sleep disruptions, etc.) be identified using a behavioural sleep/wake (S/W) monitor in the home? Sixteen women (8 good and 8 insomniac sleepers) enrolled in an introductory psychology course participated in a study of S/W patterns. They used a portable version of the Ogilvie and Wilkinson (1988) behavioural response (BR) system in their homes for 4 consecutive nights. Insomniacs had greater SOLs, less efficient sleep, and tended to have a greater number of arousals as compared with good sleepers. The data indicate that the behavioural system could be used as a diagnostic tool for in-home evaluations of disorders of initiating and maintaining sleep.

The clinical spectrum of staphylococcal bacteraemia: a review of 101 Melanesian patients from Papua New Guinea

The clinical features of 101 Melanesian patients with Staphylococcus aureus bacteraemia observed during two 2-year periods (1977-1979 and 1985-1987) in a university teaching hospital in Papua New Guinea are reviewed. The age of the patients ranged from 12 to 70 years. There were 69 males and 32 females. Diabetes mellitus, found in 15 patients, was the most common predisposing factor. Most of the patients (87%) had community-acquired infection. Soft-tissue infection, pneumonia, arthritis, osteomyelitis, intravenous-site thrombophlebitis, cerebral abscess, endocarditis and cavernous sinus thrombosis were among the clinical entities observed. Soft tissues and lungs were the most common sites of primary and secondary foci of infection, respectively. All but 1 of the 101 blood isolates were resistant to penicillin G and none was resistant to methicillin. The overall case fatality rate was 24%. These data demonstrate that staphylococcal bacteraemia in adult Papua New Guineans is mostly community acquired and has a high mortality. Skin and soft tissues are the major primary foci of infection leading to staphylococcal bacteraemia.

Effect of heparin concentration and infusion rate on the patency of arterial catheters

In a prospective randomized controlled trial involving 470 arterial catheters in 470 children, we studied the effect of changing either the concentration or the flow rate of a heparin infusion. Although catheters tended to remain patent longer with a flow rate of 2 ml/h rather than 1 ml/h, the difference was not statistically significant. Increasing the heparin concentration from 1 to 5 U/ml significantly prolonged catheter patency.

Hematogenous staphylococcal pneumonia secondary to soft tissue infection

Staphylococcal pneumonia is rare, has a high mortality and morbidity rate, and occurs commonly during influenza epidemics (airborne) or during the course of right sided bacterial endocarditis in drug addicts (blood borne). In recent years, much emphasis has been given to the staphylococcal infections in intravenous drug abusers. This report describes ten patients with staphylococcal pneumonia resulting from soft tissue infection who were previously healthy and had no history of drug abuse. They were 12 to 45 years old. Eight were male patients. Soft tissue infection was community-acquired in nine and was most commonly located in the lower extremities. Three patients had diabetes. All presented with a clinical picture of acute pneumonia. Hemoptysis occurred in three. Chest roentgenogram showed multiple large or small round discrete densities in most of the patients. Lobar involvement was notably absent. Eight developed cavitary lesions in their lungs. The average length of hospital stay was 40 days. One patient died and six developed complications. Staphylococcal etiology should be suspected in patients with acute pneumonia who have soft tissue infection or have characteristic chest roentgenogram findings; antistaphylococcal agents should be included in the therapeutic regimens of such patients until the results of the cultures are known.