Pertussis-related hyperleukocytosis: role of hyperhydration and exchange transfusion

Severe Pertussis Infection With Hyperleukocytosis in a 10-Month-Old Unvaccinated Amish Female: A Case Report

Bordetellapertussis (B. pertussis) commonly infects individuals of all ages. However, pertussis, the disease caused by B. pertussis infection, is most severe in young infants. Severe pertussis, defined by the presence of refractory hypoxemia, pneumonia, cardiogenic shock, and hyperleukocytosis, is associated with significant morbidity and mortality. Both hyperleukocytosis and pulmonary hypertension have been found to be predictive of mortality in young infants. Leukoreductive strategies such as leukapheresis and exchange transfusion have been employed to treat these complications. Pulmonary hypertension is thought to be a result of aggregation of white blood cells in pulmonary vasculature; however, studies have suggested that the mechanism of pulmonary hypertension is multifactorial. We report a case of a 10-month-old unvaccinated Amish female with pertussis complicated by an initial hyperleukocytosis of 204,900 10³/uL successfully treated with leukapheresis in our pediatric intensive care unit. This infant never showed signs of pulmonary hypertension, which is often associated with hyperleukocytosis in severe or fatal cases of pertussis in infants and neonates. To our knowledge, this is the most significant degree of hyperleukocytosis reported in pertussis. The findings in this case support the clinical utility of leukoreductive therapy in severe pertussis and provide some evidence that the mechanism of pulmonary hypertension in these patients is multifactorial.

Exchange transfusion in the management of critical pertussis in young infants: a case series

BACKGROUND AND OBJECTIVES

It is proposed that severe leucocytosis mainly contributes to pulmonary hypertension by blocking pulmonary capillaries and restricting blood flow. Exchange transfusion (ET) in pertussis has been demonstrated as a safe and useful technique for depleting the leucocyte mass. We aim to discuss four cases of pertussis-induced respiratory distress and the effectiveness of ET in such a setting.

MATERIALS AND METHODS

We conducted a retrospective case series at the Infectious Disease Department of Children's Hospital 2 in Ho Chi Minh City, Vietnam, and included four pertussis patients that were confirmed by PCR tests on respiratory secretions, presented with severe leucocytosis and respiratory distress and required mechanical ventilation.

RESULTS

Among the included patients, three underwent a double volume ET for leucodepletion, two of whom were discharged after the procedure with proper vitals and laboratory test results. On the other hand, one patient died despite ET, performed late in the course of the disease. Exchange transfusion was not performed in the last patient who died as well.

CONCLUSION

Early ET may be a useful and rapid life-saving treatment in children with critical pertussis and severe leucocytosis before cardiopulmonary complications appear.

Fatal malignant pertussis with hyperleukocytosis in a Chinese infant: A case report and literature review

RATIONALE

Pertussis has re-emerged on a global scale and is an ongoing public health problem, even in countries with high rates of vaccination. Hyperleukocytosis [white blood cell (WBC) count >100 × 10/L] is a rare complication that strongly predicts mortality in cases of severe pertussis.

PATIENT CONCERNS

We report a case of severe pertussis in an infant who initially presented with persistent cyanotic cough, tachypnea, and grunting. The infant's condition deteriorated rapidly, and she was transferred to the pediatric intensive care unit (PICU) during her third hour of hospitalization. On the third hospital day, her WBC count had increased to 101.85 × 10/L with a lymphocyte count of 36.76 × 10/L, and her hemoglobin level had fallen to 6.9 g/dL. Bone marrow examination found no evidence of tumor cells. Her initial echocardiogram showed no abnormal findings; however, a subsequent echocardiogram 10 days later revealed pulmonary hypertension.

DIAGNOSES

The patient was diagnosed with severe pneumonia, which was confirmed to be pertussis based on a persistent cough in the infant's mother and the polymerase chain reaction and culture of the infant's nasopharyngeal secretions being positive for Bordetella pertussis.

INTERVENTIONS

The infant was treated with supportive care, early macrolide antibiotics, and broad-spectrum antibiotics before being transferred to the PICU for further management, including continuous venovenous hemodiafiltration.

OUTCOMES

Unfortunately, the infant died as a result of pulmonary hypertension and multiorgan failure.

LESSONS

Exchange transfusion should be considered in all infants who present with severe pertussis with hyperleukocytosis. This guideline is supported by the findings of a comprehensive literature review, which is included in this article, as well as newly published criteria for exchange transfusion therapy. Finally, we hope that adults in China will be vaccinated against B. pertussis in order to prevent the infection of infants within their households.

An Observational Study of Severe Pertussis in 100 Infants ≤120 Days of Age

BACKGROUND

Pertussis in young infants is a unique, severe, afebrile, cough illness that is frequently fatal.

METHODS

All pertussis cases ≤120 days of age admitted to a pediatric intensive care unit in California between October 1, 2013, and April 25, 2015, were evaluated.

RESULTS

Of 100 pertussis patients ≤120 days of age admitted to pediatric intensive care unit, there were 5 deaths. The white blood cell counts in the fatal cases were significantly higher than in the nonfatal cases. Thirty-four percent of patients were intubated, 18% received inotropic and/or vasoactive support, 22% received steroid, 4% received extracorporal membrane oxygenation, and 3% underwent exchange blood transfusion. The median age at the time of illness onset in the patients who died was 23 days.

CONCLUSIONS

These data, as well as data from previous California studies, suggest updated strategies for the management of severe pertussis. These include perform serial white blood cell counts, treat all presumptive cases with azithromycin, evaluate for pulmonary hypertension, intubate and administer oxygen for apneic episodes and administer inotropic/vasoactive agents for cardiogenic shock. Do not administer steroids or nitric oxide. Criteria for exchange blood transfusion therapy for leukocytosis with lymphocytosis are suggested.

The use of cytapheresis in the treatment of infectious diseases

Cytapheresis (removal of cellular blood components) has been employed for treatment of infectious diseases since the 1960s. Techniques have included thrombocytapheresis (buffy coat apheresis) for loiasis, erythrocytapheresis for malaria and babesiosis, and leukocytapheresis for pertussis-associated lymphocytosis. Published data on these applications is largely limited to case level data and small observational studies; as such, recommendations for or against the use of cytapheresis in the treatment of infections have been extrapolated from these limited (and at times flawed) data sets. Consequently, utilization of cytapheresis in many instances is not uniform between institutions, and typically occurs at the discretion of treating medical teams. This review revisits the existing literature on the use of cytapheresis in the treatment of four infections (loasis, malaria, babesiosis, and pertussis) and examines the rationale underlying current treatment recommendations concerning its use.

Leukemoid Reaction in Infant Pertussis: Is There a Place for Hydroxyurea? A Case Report

A 73-days old infant of 34 weeks' gestation was hospitalized with a co-infection of respiratory syncytial virus (RSV) and Bordetella pertussis (BP). She required invasive ventilation for 9 days in the context of malignant pertussis with persistent hypoxemia and hypercapnia secondary to a leukemoid reaction. Despite an increase of white blood cell (WBC) count up to 70 G/L and ensuing pulmonary hypertension, no hemodynamic compromise occurred. Without clear indication for leukapheresis nor exchange transfusion, an off-label treatment with hydroxyurea was given for 5 days with gradual decrease of WBC count, without any complication and hospital discharge on day 29. To our knowledge, no effective therapy for malignant pertussis has been described in the literature and complications are frequent with leukoreduction procedures. We discuss an alternative to invasive procedures in young infants to fulfill the need to decrease rapidly leukocyte counts in a leukemoid reaction associated with Bordetella pertussis infection. To our knowledge, hydroxyurea has never been used in malignant pertussis but is a well-known medication for oncologic and hematologic diseases such as acute myeloid leukemia or sickle cell anemia. Its effects in this setting are not well understood but the positive outcome in our patient supports the need for further studies.

Pertussis leukocytosis: mechanisms, clinical relevance and treatment

The significant and sometimes dramatic rise in the number of circulating white blood cells (leukocytosis) in infants suffering from pertussis (whooping cough) has been recognized for over a century. Although pertussis is a disease that afflicts people of all ages, it can be particularly severe in young infants, and these are the individuals in whom leukocytosis is most pronounced. Very high levels of leukocytosis are associated with poor outcome in infants hospitalized with pertussis and modern treatments are often aimed at reducing the number of leukocytes. Pertussis leukocytosis is caused by pertussis toxin, a soluble protein toxin released by Bordetella pertussis during infection, but the exact mechanisms by which this occurs are still unclear. In this minireview, I discuss the history of clinical and experimental findings on pertussis leukocytosis, possible contributing mechanisms causing this condition and treatments aimed at reducing leukocytosis in hospitalized infants. Since recent studies have detailed significant associations between specific levels of pertussis leukocytosis and fatal outcome, this is a timely review that may stimulate new thinking on how to understand and combat this problem.

Pertussis in the newborn: certainties and uncertainties in 2014

Bordetella pertussis infection remains a serious potential health risk to infants, specially in those too young to be vaccinated. Over the recent years, numerous sources highlighted a widespread resurgence, making it, again, a challenging disease. Globally, pertussis is ranked among the 10 leading causes of childhood mortality. This review summarizes the most recent literature and will address the most important aspects that pediatricians and neonatologists must be familiar with, when treating a newborńs pertussis infection.

Role of therapeutic apheresis in infectious and inflammatory diseases: Current knowledge and unanswered questions

Apheresis can remove pathogens and mediators that contribute to pathogenic inflammatory responses in diseases not generally considered to be "Hematologic." Erythrocytapheresis can remove intracellular pathogens such as Babesiosis. Plasmapheresis can remove mediators of the inflammatory response in conditions such as sepsis, chronic autoimmune urticaria and malignant pertussis. Leukapheresis can remove potentially harmful leukocytes in Crohn's Disease and malignant pertussis. While apheresis can remove all of these substances, the clinical efficacy and pathophysiologic changes that occur during apheresis in these conditions are largely unknown. Hence, the clinical utility of apheresis in these conditions is largely unknown and research in these areas has the potential to benefit many patients with a variety of diseases.

Neonatal extracorporeal membrane oxygenation: Initial experience of Hospital de São João

The purpose of this series is to report the initial ECMO experience of the Neonatal Intensive Care Unit of Hospital de São João. The first three clinical cases are reported. Case report 1: a 39 weeks gestational age girl with severe lung hypoplasia secondary to a bilateral congenital diaphragmatic hernia. Case report 2: a 39 weeks gestational age girl with a right congenital diaphragmatic hernia and a tracheal stenosis. Case report 3: a 34 weeks gestational age boy, with 61 days of life, with a Bordetella pertussis pneumonia, severe pulmonary hypertension, shock, hyperleukocytosis and seizures.

Severe pertussis in newborns and young vulnerable infants

A retrospective chart review of 18 nonvaccinated newborns and infants admitted to 6 intensive care units in the north of Portugal between 2007 and 2012 revealed a high rate of admissions in 2012 along with significant rates of severe pulmonary hypertension and mortality. Hyperleukocytosis was significantly associated with a more severe clinical picture and mortality.