Diagnosis of pneumonia: A shared need

Pneumonia is currently one of the most common infectious diseases and the condition that causes the greatest morbidity and mortality in adults and children¹. According to data published by the National Institute of Statistics², in 2019 pneumonia caused more than 9300 deaths in Spain, representing 2.24% of total deaths.

In different studies, the crude mortality rate of patients with hospital-aquired pneumonia ranges from 30% to 70%³. The classic series by Luna et al.⁴ points to a significant decrease in the crude mortality rate from 92.2% to 37.5%, depending on whether the prescribed antibiotic treatment was adequate or inadequate. For this reason, a rapid microbiological diagnosis is essential for adequate and targeted antimicrobial treatment.

Currently, an aetiological diagnosis is not reached for 30%–50% of patients (especially in community-acquired pneumonia) and the initial treatment is totally empiric⁵. This is mainly due to the fact that many patients have been on antimicrobial treatment prior to the respiratory sample being taken, which reduces the possibility of recovering the microorganism by conventional microbiological methods (Gram stain and culture).

In addition, traditional identification and culture procedures are a slow and poorly-performing methodology that sometimes provide delayed results, leading to inadequate therapies⁶.

In recent years, we have witnessed technological progress in the area of microbiological diagnosis that permits better patient management, offering more accurate and faster results. However, molecular biology technologies (currently widely used to detect respiratory viruses) for the diagnosis of bacterial pneumonia are rarely used, despite their availability⁷, partly due to outdated funding models, despite the fact that their clinical impact when applied in conjnction with therapeutic optimisation programmes is high, as documented by Chastre and Fagon, demonstrating a decrease in in-hospital mortality⁸. There are solid reflections that advocate this reality where the effects obtained exceed the costs generated⁹.

To apply these new rapid molecular syndromic diagnosis technologies in the field of pneumonia, five actions would need to be promoted:

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  Update overall guidelines and hospital protocols with ASPs (antibiotic stewardship programmes) and define algorithms for use and optimal treatments.

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  Provide microbiology departments with the necessary technology to carry out the microbiological diagnosis of pneumonia.

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  Guarantee the availability of continuous microbiological diagnosis and advice 24 h a day, seven days a week.

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  Reorganise information flows to ensure the greatest clinical impact with the rapid transmission of microbiology results and their interpretation in conjunction with the application of ASPs.

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  Implement funding models for these technologies according to the value they provide, taking into account that they generate very valuable information, thus enabling optimal use of health resources.

From the healthcare system manager's standpoint, a rapid test for diagnosing infectious diseases should have high sensitivity and specificity, be simple to perform and interpret, not be invasive for the patient, not require a large number of professionals or highly-complex technology, deliver high performance in a point-of-care model and which would make it possible to differentiate between colonisation and infection.

The implementation of rapid microbiological diagnosis strategies and protocols for hospital-acquired pneumonia based on molecular detection can be an essential aid in order to improve clinical practice in seriously ill patients, with decompensated underlying diseases, at extreme ages and in patients treated in critical units¹⁰.

In summary, the management of patients with pneumonia must guarantee a multidisciplinary team where communication flows, and which includes clinicians, microbiologists and pharmacists in the management of the patient, with rapid microbiological diagnostic techniques available that allow the antimicrobial treatment to be adapted, since the administration of early appropriate antibiotic therapy is the main modifiable factor that improves survival.

Funding

The authors are members of the GEDRA [Grupo de Expertos de Diagnóstico Rápido Avanzada (Group of Experts on Advanced Rapid Diagnostics)] and have received consultancy fees from bioMérieux Spain.