Early management of meningococcal disease

Clinical spectrum and short-term outcome of adult patients with purpura fulminans: a French multicenter retrospective cohort study

PURPOSE

Data on purpura fulminans (PF) in adult patients are scarce and mainly limited to meningococcal infections. Our aim has been to report the clinical features and outcomes of adult patients admitted in the intensive care unit (ICU) for an infectious PF, as well as the predictive factors for limb amputation and mortality.

METHODS

A 17-year national multicenter retrospective cohort study in 55 ICUs in France from 2000 to 2016, including adult patients admitted for an infectious PF defined by a sudden and extensive purpura, together with the need for vasopressor support. Primary outcome variables included hospital mortality and amputation during the follow-up period (time between ICU admission and amputation, death or end of follow-up).

RESULTS

Among the 306 included patients, 126 (41.2%; 95% CI 35.6-46.9) died and 180 (58.8%; 95% CI 53.3-64.3) survived during the follow-up period [13 (3-24) days], including 51/180 patients (28.3%, 95% CI 21.9-35.5) who eventually required limb amputations, with a median number of 3 (1-4) limbs amputated. The two predominantly identified microorganisms were Neisseria meningitidis (63.7%) and Streptococcus pneumoniae (21.9%). By multivariable Cox model, SAPS II [hazard-ratio (HR) = 1.03 (1.02-1.04); p < 0.001], lower leucocytes [HR 0.83 (0.69-0.99); p = 0.034] and platelet counts [HR 0.77 (0.60-0.91); p = 0.007], and arterial blood lactate levels [HR 2.71 (1.68-4.38); p < 0.001] were independently associated with hospital death, while a neck stiffness [HR 0.51 (0.28-0.92); p = 0.026] was a protective factor. Infection with Streptococcus pneumoniae [sub-hazard ratio 1.89 (1.06-3.38); p = 0.032], together with arterial lactate levels and ICU admission temperature, was independently associated with amputation by a competing risks analysis.

CONCLUSION

Purpura fulminans carries a high mortality and morbidity. Pneumococcal PF leads to a higher risk of amputation.

TRIALS REGISTRATION

NCT03216577.

[Management of purpura fulminans lesions in children]

Purpura fulminans is a pediatric life-threatening emergency with a significant mortality, combining: septic shock, extensive purpuric lesions and disseminated intravascular coagulation. The most frequent bacterial pathogen is the meningococcus. The medical management includes antibiotics, corticoids, vascular filling and catecholamines. Purpura fulminans is characterized by the extent of hemorrhagic and mainly thrombotic lesions, attributed to the alteration in the vascular endothelium functions. Damage of soft tissues combines large necrotic areas and more or less extensive distal ischemic lesions. Necrotic lesions can be deep, reaching skin, subcutaneous tissue, fascia, muscle and sometimes even the bone. The importance of the aesthetic and functional sequelae as well as future quality of life, depend on the quality of surgical management for these wide and deep lesions. Fasciotomy is sometimes urgently needed in the case of a clinical compartment syndrome, confirmed by a high-pressure measurement in the muscle compartments. Debridement of necrotic lesions and amputations are only performed after a clear delineation of necrotic areas, between 10 days and 3 weeks of evolution. If an amputation is necessary, it must focus on the residual bone length, considering the child's growth potential. The coverage of tissue loss uses all the plastic surgery techniques, more or less complex, in order to reduce scars to minimum for these children. Rehabilitation follow-up includes physical and psychological care, which are essential until adulthood.

Modern trends in mortality from meningococcal disease in Australia

Between 1979 and 2006, there were 610 deaths recorded as due to meningococcal disease in Australia. Mortality rates per capita consistently increased on average by 6% per annum between 1979 and 2002, but then fell significantly in 2003, coinciding with the introduction of the meningococcal C conjugate vaccine. In 2002, the mortality rate was 0.24 per 100,000. In the 4 years since, it fell progressively to 0.06 per 100,000. Since the introduction of conjugate Hib and pneumococcal vaccines, meningococcal disease has emerged as the number 1 infectious cause of death in children but conjugate meningococcal C vaccine appears to have greatly reduced total meningococcal disease deaths.

Quality assessed nonculture techniques for detection and typing of meningococci

PCR protocols are increasingly used in laboratories worldwide for the diagnosis and confirmation of invasive meningococcal infection. Protocols are now available for the identification of Neisseria meningitidis, for genogrouping, susceptibility to antibiotics and genotyping of the corresponding isolates. The implementation of quality assurance (QA) schemes and standardization of protocols are required. Diagnostic and confirmatory PCRs should perform consistently in clinical and reference microbiology laboratories. General QA schemes address the issues of sample preparation, PCR laboratory environment, equipment and validation of protocols. Moreover, external QA interlaboratory studies are essential. The European Monitoring Group on Meningococci has provided a good forum to conduct such studies through the development and distribution of samples and protocols for nonculture detection and typing of N. meningitidis.

Standardized nonculture techniques recommended for European reference laboratories

Culture-confirmed diagnosis of meningococcal invasive infections is often hindered by early antibiotic treatment. Nonculture molecular standardized methods are now essential tools for the immediate management of meningococcal infections. The European Monitoring Group on Meningococci (EMGM) recommends the following measures. (1) The implementation of standardized protocols of extraction methods for DNA isolation from clinical specimens for PCR-based identification and genogrouping of Neisseria meningitidis. (2) The use of molecular approaches (sequencing of target genes) for the determination of meningococcal susceptibility to antibiotics, such as sequencing of penA and rpoB genes for susceptibility to penicillin G and rifampicin, respectively. (3) The use of nonculture strain characterization by multilocus sequence typing (MLST) and sequence typing of porA and fetA. These approaches can be implemented either by individual reference laboratories or through collaboration and referral between centres.

Variations in case fatality and fatality risk factors of meningococcal disease in Western Norway, 1985-2002

In a retrospective epidemiological study, 293 meningococcal disease patients hospitalized during 1985-2002, were examined for fatality and risk factors related to death. The overall case fatality rate (CFR) was 8.2%, but increased from 4% during 1985-1993 to 17% during 1994-2002. The latter 9-year period was characterized by more serogroup C infections and more patients with thrombocytopenia on admission to hospital. All patients categorized as meningitis on admission survived. Of the 24 patients who died, 21 had meningococcal skin rash on admission, 23 had an onset to admission time of < or =24 h, and 16 had severe septicaemia with hypotension and/or ecchymoses without meningitis on admission. By multivariate analyses, a short onset to admission time, >50 petechiae, thrombocytopenia and severe septicaemia on admission were associated with fatality. More lives could be saved through earlier admission to hospital. This can be achieved through more information to the public about the early signs of meningococcal septicaemia, with the recommendation to look for skin rash in patients with acute fever during the first day and night.

Interlaboratory comparison of PCR-based identification and genogrouping of Neisseria meningitidis

Twenty clinical samples (18 cerebrospinal fluid samples and 2 articular fluid samples) were sent to 11 meningococcus reference centers located in 11 different countries. Ten of these laboratories are participating in the EU-MenNet program (a European Union-funded program) and are members of the European Monitoring Group on Meningococci. The remaining laboratory was located in Burkina Faso. Neisseria meningitidis was sought by detecting several meningococcus-specific genes (crgA, ctrA, 16S rRNA, and porA). The PCR-based nonculture method for the detection of N. meningitidis gave similar results between participants with a mean sensitivity and specificity of 89.7 and 92.7%, respectively. Most of the laboratories also performed genogrouping assays (siaD and mynB/sacC). The performance of genogrouping was more variable between laboratories, with a mean sensitivity of 72.7%. Genogroup B gave the best correlation between participants, as all laboratories routinely perform this PCR. The results for genogroups A and W135 were less similar between the eight participating laboratories that performed these PCRs.

Molecular genetic methods in diagnosis and direct characterization of acute bacterial central nervous system infections

Acute bacterial infection of the central nervous system requires rapid and adequate management. Etiological diagnosis is hence crucial. Moreover, the epidemic threat of certain bacteria necessitates a reliable characterization of the involved bacterial strains to follow the spread of epidemic strains. Conventional identification and characterization of etiological agents are basically based on culture and identification of bacterial markers most frequently by serological assays. Molecular identification and characterization of bacteria have been employed. They provide more reliable analysis of bacterial isolates. Molecular methods for non-culture diagnosis of bacterial infections have recently been developed. In many cases, the molecular assays have decreased the identification time of positive cultures and rescued detection of pathogens in culture-negative clinical samples.

Evaluation of a rapid PCR assay for diagnosis of meningococcal meningitis

We compared the results of Gram staining and culture of cerebrospinal fluid to results obtained with a rapid PCR assay for the diagnosis of meningococcal meningitis in 281 cases of suspected bacterial meningitis. PCR had a sensitivity of 97% compared to a sensitivity of 55% for culture, and the PCR specificity was 99.6%. PCR results were available within 2 h of the start of the assay.

Meningococcal disease and travel

Invasive meningococcal disease, in both endemic and epidemic forms, is the cause of significant morbidity and mortality worldwide. Despite all advances in therapy, the fatality rate of meningococcal meningitis remains unacceptably high, between 5% and 10%, and a similar proportion suffers long-term neurological sequalae. Prevention of this rapidly fatal disease is of paramount importance. The use of the available internationally licensed meningococcal vaccines would be indicated for individuals with medical conditions that increase the risk of the disease and for travelers to high-risk countries. In the last 2 years, there has been a shift in the epidemic pattern of meningococcal disease during the Hajj (pilgrimage) season, with predominance of Neisseria meningitidis serogroup W135. Recent changes have been made in the policy issued by the Saudi Ministry of Health (Riyadh, Saudi Arabia), which requires visitors from all over the world arriving for purposes of umra and Hajj to show evidence of vaccination against meningitis with the quadrivalent meningococcal vaccine.

[Treatment of meningococcal purpura fulminans]

In France, the incidence of meningococcal infections is increasing. The most severe presentation, called purpura fulminans, has a death rate of 20-25%; 5 to 20% of the survivors need skin grafts and/or amputations. Diagnosis of invasive meningococcal infection is very difficult when purpura and "toxic" appearance are absent: one should take into account parents' impression of their ill child. This diagnosis must be evoked in any child presenting with febrile purpura (like in the United Kingdom, parents should be encouraged to use the "tumbler test" to identify a vasculitic rash); a fulminant form is to be suspected in the presence of only one ecchymosis and signs of infection, remembering that recognition of shock is difficult in children. Recently, the Health Authority has recommended to administer a third generation cephalosporin promptly (before biological investigations) for any child with signs of infection and a necrotic or ecchymotic purpura (> 3 mm of diameter), and then to refer the patient to the hospital. By grouping the patients from 7 studies, it can be observed that preadmission antibiotic administration has a protective effect on mortality (odds ratio: 0.36; 95% confidence interval: 0.23-0.56); a negative effect was observed in only one of these series. Children with purpura fulminans should be referred to a paediatric intensive care unit. Management includes antibiotics, steroids, fluid resuscitation and catecholamines (be aware of hypoglycaemia, particularly in infants, and hypocalcaemia). Treatment of cutaneous necrosis and distal ischemia is difficult and still controversial: antithrombin, protein C, tissue plasminogen activator and vasodilator infusion have no proven efficacy. Cases must be rapidly notified to the Public Health Service who will institute chemoprophylaxis for close contacts. Given the predominance of serogroup B in France, we hope that an efficient vaccine will soon become available.

Can generic scores (Pediatric Risk of Mortality and Pediatric Index of Mortality) replace specific scores in predicting the outcome of presumed meningococcal septic shock in children?

OBJECTIVE

To compare, in children with septic shock and purpura, the accuracy in predicting death of two specific scores (the MenOPP bedside clinical [MOC] score of Gedde Dahl and the score of Groupe Francophone de Réanimation Pédiatrique [GFRP]), the C-reactive protein (CRP) level, and the two pediatric generic scores (the Pediatric Risk of Mortality [PRISM] and Pediatric Index of Mortality [PIM] scores).

DESIGN

Prospective, population-based study with analysis of previous comparative studies.

SETTING

A 14-bed pediatric intensive care unit in a university hospital.

PATIENTS

All children admitted consecutively to the pediatric intensive care unit with septic shock and purpura (n = 58, with 16 deaths [27.6%]) from January 1993 to May 2000.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The MOC and GFRP scores and the CRP level were prospectively determined at admission. The PRISM score was prospectively calculated within 24 hrs of admission or at the time of death, and the PIM score was calculated retrospectively between 1993 and 1997 and then prospectively from admission data. The nonparametric estimate of the area under the receiver operating characteristic curves (AUC) was calculated from the raw data using the Wilcoxon-Mann-Whitney two-sample statistic, and the standard error of the AUCs was calculated with DeLong's method. All the scores had an AUC >0.80, the PRISM probability of death having the best one (0.96 +/- 0.02). The PRISM value, which is easier to calculate, had an AUC of 0.95 +/- 0.02. The PRISM score performed significantly better than the PIM score (AUC, 0.83 +/- 0.06; p <.01) and the CRP level (AUC, 0.80 +/- 0.06; p <.01); however, there was no significant difference between the MOC (AUC, 0.91 +/- 0.04) and GFRP scores (AUC, 0.87 +/- 0.05). Analyzing literature and calculating AUCs from original data of previous studies, we observed that the superiority of the PRISM score had never been demonstrated in meningococcal diseases.

CONCLUSIONS

The PRISM score performed better than the PIM score, and was not surpassed by specific scores. Thus, we propose its use for outcome prediction in children with septic shock and purpura. However, if the PRISM score is to be used as inclusion criterion for clinical trials, it should be evaluated within a few hours after admission.

Improving the outcome of septic shock in children

Sepsis is an important cause of pediatric morbidity and mortality. Improving the outcome of pediatric sepsis requires diverse efforts, including prevention, early recognition, improvements in early management and transport, and physiology-directed care. Awareness that septic shock represents a pathophysiologic host response to infection has prompted investigation of immune mediators and coagulation factors as potential targets for anti-sepsis therapies. Advancements thus far include: the potential prevention of neonatal sepsis with granulocyte colony-stimulating factor; recognition of clindamycin as a potential inhibitor of endotoxin release; improved outcome from meningococcal disease in children treated with bactericidal/permeability-increasing protein (rBPI21); and improved outcome from sepsis in premature infants treated with pentoxifylline. Further randomized controlled studies of immunomodulatory agents are indicated and a few are in progress. Current studies on genetic propensities in cytokine and coagulation protein expression may explain variability in patient outcomes and eventually lead to genomics-based therapeutics.