Clinicopathological findings in fulminant-type pneumococcal infection: Report of three autopsy cases

FilmArray® meningitis/encephalitis (ME) panel, a rapid molecular platform for diagnosis of CNS infections in a tertiary care hospital in North India: one-and-half-year review

BACKGROUND

Acute meningitis and encephalitis (AME) is a syndrome of central nervous system (CNS) infections, which could lead to neurological damage and fatality. This study evaluates the multiplex FilmArray® ME Panel which is aimed to diagnose agents causing suspect CNS infections in north India.

METHODS

A total number of 969 cerebrospinal fluid (CSF) samples collected between August 2016 and January 2018 from patients who showed clinical symptoms of CNS infections were analyzed using the FilmArray® ME Panel. Also a comparison of molecular diagnosis and various laboratory and radiological findings for Streptococcus pneumoniae, Enterovirus and Cryptococcus neoformans positive cases was done.

RESULT

Out of the 969 CSF samples, 101 cases were found to be positive for viral (n = 55), bacterial (n = 38), fungal (n = 7), and poly-microbial (n = 1) agents. Out of the 55 viral positive cases, the most detected pathogen was Enterovirus (n = 23) with predominance in the age group of 2-17 years, followed by Varicella Zoster virus (n = 14) and HSV1(n = 9) cases. Streptococcus pneumoniae (n = 26) was found to be the predominant bacterial pathogen, of which 17 were detected in the age group above 35 years. Cryptococcus neoformans was found in 7 cases.

CONCLUSION

The FilmArray® ME Panel aids in rapid detection of 14 pathogens directly from CSF. When compared to gram stain, culture, antigen detection, and CSF biochemical analysis, the FilmArray® ME Panel has detected more cases, some of which are difficult to diagnose by conventional methods. This rapid technology will help the clinicians in case of early patient management, outcomes and provide aid in antimicrobial stewardship.

Fatal overwhelming postsplenectomy infection due to Streptococcus pneumoniae serotype 10A with atypical polysaccharide capsule in a patient with chromosome 22q11.2 deletion syndrome: A case report

We report the first case of a teenage patient with chromosome 22q11.2 deletion syndrome who died of overwhelming postsplenectomy infection (OPSI) by Streptococcus pneumoniae despite appropriate prevention by pneumococcal vaccine. He had congenital heart disease and underwent several surgeries. Immunodeficiency had not been noticed clinically. Two years prior to death, splenectomy was performed for a drug-resistant idiopathic thrombocytopenic purpura and he was immunized with 23-valent pneumococcal polysaccharide vaccine (PPV23) 4 months after splenectomy. He died suddenly after a mild flu-like symptom. Autopsy was performed and OPSI was diagnosed. Blood culture was positive for S. pneumoniae. This isolated S. pneumoniae strain was serotypically un-typable by polyvalent serum agglutination test. On the contrary, multilocus sequence typing followed by DNA sequencing indicated the molecular serotype as 10A. Additional testing using monovalent and factor-specific sera confirmed the strain as serotype 10A. Ultrastructural observation of this S. pneumoniae strain showed that the polysaccharide capsule was thin and sparse. We speculate that the abnormal morphology of the capsule may have accounted for the polyvalent serum agglutination failure and may possibly be associated with severity of OPSI observed in this case. Chromosome 22q11.2 deletion syndrome is associated with certain immunodeficiency, especially susceptible to S. pneumoniae infections; however, fatal OPSI has not been reported. In addition to vaccination, prophylactic antibiotics may be necessary for these patients who are at risk of immunodeficiency.

Pneumonia: Features registered in autopsy material

BACKGROUND

Despite improvements in clinical practice, pneumonia remains one of the leading causes of death worldwide. Pathologic findings from autopsy reports could provide more precise and valid data on characteristics of pneumonia patients.

METHODS

We retrospectively reviewed autopsy reports of deceased patients admitted to the Institute for Pulmonary Diseases of Vojvodina in Sremska Kamenica, Serbia, between 1994 and 2003. The patients were classified into two groups: group 1 (n = 161) comprised patients in whom pneumonia was the main cause of death, while group 2 (n = 165) consisted of patients in whom pneumonia was confirmed at autopsy but had various different causes of death.

RESULTS

From 1776 patients who underwent autopsy 326 (18.3%) were diagnosed with pneumonia. The most common underlying diseases were atherosclerosis (29.4%), chronic obstructive pulmonary disease (COPD) (26.7%), and malignancies (20.2%). Pneumonia was the main cause of death in 161 cases (group 1) while in group 2 major causes of death were heart failure (HF) (26.7%), acute myocardial infarction (AMI) (16.4%), and pulmonary embolism (PE) (10.9%). Multilobar involvement (91% vs.27%), pulmonary effusion (29% vs.14%), and lung abscess (23.6% vs.8.5%) were more frequently found in group 1, compared to group 2.

CONCLUSION

In patients with pneumonia who underwent autopsy most common underlying diseases were atherosclerosis, COPD, and malignancies, while major causes of death were: progression of pneumonia, HF, AMI, and PE.

Causes and consequences of coagulation activation in sepsis: an evolutionary medicine perspective

BACKGROUND

Coagulation and innate immunity have been linked together for at least 450 million years of evolution. Sepsis, one of the world's leading causes of death, is probably the condition in which this evolutionary link is more evident. However, the biological and the clinical relevance of this association have only recently gained the attention of the scientific community.

DISCUSSION

During sepsis, the host response to a pathogen is invariably associated with coagulation activation. For several years, coagulation activation has been solely regarded as a mechanism of tissue damage, a concept that led to several clinical trials of anticoagulant agents for sepsis. More recently, this paradigm has been challenged by the failure of these clinical trials, and by a growing bulk of evidence supporting the concept that coagulation activation is beneficial for pathogen clearance. In this article we discuss recent basic and clinical data that point to a more balanced view of the detrimental and beneficial consequences of coagulation activation in sepsis. Reappraisal of the association between coagulation and immune activation from an evolutionary medicine perspective offers a unique opportunity to gain new insights about the pathogenesis of sepsis, paving the way to more successful approaches in both basic and clinical research in this field.

Community-acquired pneumonia: identification and evaluation of nonresponders

Community acquired pneumonia (CAP) is a relevant public health problem, constituting an important cause of morbidity and mortality. It accounts for a significant number of adult hospital admissions and a large number of those patients ultimately die, especially the population who needed mechanical ventilation or vasopressor support. Thus, early identification of CAP patients and its rapid and appropriate treatment are important features with impact on hospital resource consumption and overall mortality. Although CAP diagnosis may sometimes be straightforward, the diagnostic criteria commonly used are highly sensitive but largely unspecific. Biomarkers and microbiological documentation may be useful but have important limitations. Evaluation of clinical response is also critical especially to identify patients who fail to respond to initial treatment since these patients have a high risk of in-hospital death. However, the criteria of definition of non-response in CAP are largely empirical and frequently markedly diverse between different studies. In this review, we aim to identify criteria defining nonresponse in CAP and the pitfalls associated with this diagnosis. We also aim to overview the main causes of treatment failure especially in severe CAP and the possible strategies to identify and reassess non-responders trying to change the dismal prognosis associated with this condition.

Autopsy cases of fulminant bacterial infection in adults: clinical onset depends on the virulence of bacteria and patient immune status

To assist physicians in recognizing the potentially fatal onset of symptoms in cases of fulminant bacterial infection, we analyzed 11 autopsy cases of such infection (four caused by Streptococcus pneumoniae, four by S. pyogenes, one by S. dysgalactiae subsp. equisimilis, one by Staphylococcus aureus, and one by Vibrio vulnificus). Clinicohistopathologic features were evaluated. All patients experienced sudden onset of hypotension and multiple organ failure, leading to unexpected death. Blood culture confirmed bacteremia. The main chief complaints were gastrointestinal symptoms (45%) and limb pain (36%). All had an underlying chronic illness (82%), e.g., a hematologic disorder (36.3%) or liver cirrhosis (27.2%). Necrotizing fasciitis occurred in only 55% of cases, with none involving pneumococcal infection. Laboratory tests typically showed C-reactive protein elevation but without leukocytosis, indicating a high-level inflammatory state. In ten cases, death was attributed to circulatory collapse due to sepsis; severe pulmonary congestion and hemorrhage were present in these cases. The onset of fulminant bacterial infection depends on both virulence of the bacterium and status of the host defense system.

Sudden death caused by fulminant bacterial infection: background and pathogenesis of Japanese adult cases

OBJECTIVE

To analyze a risk factor for the onset of fulminant bacterial infection.

PATIENTS AND METHODS

Nine unexpected acute death cases were clinicopathologically analysed. All cases represented the sudden onset of shock symptom, led to acute death within a few days, and later bacteremia was identified. Pathogens were Streptococcus pneumoniae (S. pneumoniae) (5 cases), group A beta Hemolytic Streptococcus pyogenes (S. pyogenes) (3 cases), and Vibrio vulnificus (V. vulnificus) (1 case).

RESULTS

Seven of the nine patients had underlying chronic illness. S. pneumoniae infection was associated with splenic dysfunction, and group A beta Hemolytic S. pyogenes and V. vulnificus infections were associated with alcoholic liver injury. Group A beta hemolytic S. pyogenes and V. vulnificus infections involved necrotizing fasciitis, and alcoholic liver cirrhosis was confirmed in two of the four patients.

CONCLUSION

Despite the different type of bacteria, the onset of fulminant bacterial infection depended upon depressed bacterial phagocytosis in the liver or spleen. Underlying chronic illnesses should be identified as a predisposing common risk factor. It is important to understand the relations between underlying chronic illness and the onset of fulminant infection.