Zoonotic infections as causes of hospitalization among febrile Bedouin patients in southern Israel

Serologic Diagnosis of Acute Rickettsiosis in Children in Southern Israel

We assessed serology results of clinically suspected rickettsiosis episodes in the hospital setting. Overall, 322 of 963 (33%) cases were serology positive. Among those, rash rates were low (30%), murine typhus (MT) predominated over spotted fever and IgM positivity rate was higher in MT. These findings suggest that during acute rickettsiosis, serology may reliably identify MT infection but may underdiagnose spotted fever.

The implications of Rose Bengal test seroconversion in the diagnosis of brucellosis in children in an endemic region

BACKGROUND

The Rose Bengal test (RBT) is a commonly used simple serological test for brucellosis. We assessed brucellosis in individuals <18 years for RBT performance; duration of RBT positivity following infection; and potential factors associated with RBT seroconversion timing.

METHODS

The medical files of first hospital admissions of brucellosis, 2005-2014, southern Israel, were retrospectively reviewed.

RESULTS

Overall, RBT was positive in 99% of 416 primary brucellosis admissions. The mean age was 9.8 ± 4.5 years; all patients were of Bedouin ethnicity. Of 273 patients with subsequent RBT testing, RBT remained positive in 169 cases (duration range: 0.1-122 months). Overall, 104 patients had subsequent negative RBT result (duration range: 0.9-127; median: 29.9 months). Comparing fast (<30 months) vs. slow (≥30 months) seroconversion, IgM titres ≥1:640 were more common in fast seroconversion episodes (53% vs. 23%, p = .003). Anaemia was more common in the slow seroconversion group (76% vs. 52%, p = .02). Age, gender, ethnicity, fever, arthralgia, thrombocytopenia, leukopenia, liver enzymes, bacteraemia and adequate treatment rates were similar.

CONCLUSIONS

RBT positivity rate in first hospital visit was high. Fast negative seroconversion was associated with high IgM titres and lower anaemia rates at first presentation. These findings may assist early recognition of long-lasting brucellosis patients in endemic regions.

Factors Associated With Single and Recurrent Bacteremia in Childhood Brucellosis

BACKGROUND

Data regarding risk factors of bacteremic brucellosis, and specifically recurrent bacteremia, are scarce. We assessed patients with childhood brucellosis, differentiating between those having culture-negative, single-bacteremic, and recurrent-bacteremic episodes.

METHODS

The medical files of pediatric brucellosis patients, from 2005 through 2014, were reviewed retrospectively. Univariate and multivariate analyses were performed to compare demographic and clinical characteristics of culture-negative, single-bacteremic, and recurrent-bacteremic (≥30 days between positive cultures) episodes.

RESULTS

Of all 436 brucellosis cases, 22% were culture-negative, 72% were single-bacteremic, and 6% were recurrent-bacteremic. In a univariate analysis, single-bacteremic episodes were associated with fever (90% vs 65% and 40% in culture-negative and recurrent bacteremia, respectively) and elevated glutamic oxaloacetic transaminase (GOT) levels. Recurrent-bacteremic episodes were associated with anemia (26% vs 14% and 9% in single bacteremia and culture negative, respectively), elevated GOT, low immunoglobulin M (IgM) titers (56% vs 89% and 99%, respectively), and lower levels of adequate treatment (74% vs 94% and 86%, respectively). In multivariate analyses, single bacteremia was associated with fever (odds ratio [OR], 3.595, compared with culture negative), while recurrent bacteremia was inversely associated with IgM titers ≥1:160 (OR, 0.022 and 0.226 compared with culture negative and single bacteremia, respectively) and fever (OR, 0.108 compared with single bacteremia).

CONCLUSIONS

Brucellosis episodes are commonly complicated with bacteremia. Single-bacteremic episodes were associated with high-grade fever and elevated liver enzymes, possibly indicating high bacterial virulence. Recurrent-bacteremic episodes were associated with poor treatment at initial diagnosis, along with low rates of fever, low IgM titers, and high anemia rates, possibly indicating impaired host response. Physicians should consider treatment modifications for suspected recurrent-bacteremic brucellosis, including monitoring treatment adherence, and possibly administering prolonged treatment.

Hematologic Manifestations of Brucellosis in Children

BACKGROUND

Brucellosis is a common zoonosis in the Bedouin population of southern Israel. Limited data exist for the rate and risk factors of hematologic complication of brucellosis in children. We assessed anemia, leukopenia, thrombocytopenia and pancytopenia in childhood brucellosis in southern Israel.

METHODS

Our medical center is the sole hospital in southern Israel. All medical files of brucellosis, 2005-2014, identified through positive blood cultures or International Classification of Diseases 9th revision coding with positive serology, were reviewed retrospectively.

RESULTS

Overall, 511 brucellosis episodes were identified; 42% (N = 214) with ≥1 cytopenia, including 13% (N = 68) anemia, 28% (N = 144) leukopenia, 14% (N = 74) thrombocytopenia and 2% (N = 9) pancytopenia. Overall, 99.8% of episodes were in Bedouin children and 70% in males. In 79% of episodes, blood culture was positive for Brucella melitensis. Acute infections comprised 84% of all episodes. In univariate analysis, older age (10.49 ± 4.81 vs. 9.25 ± 4.89 years), fever (92% vs. 78%), positive blood culture (84% vs. 75%) and IgM ≥1:640 levels (50% vs. 39%) were associated with cytopenia. In contrast, arthralgia was associated with noncytopenic episodes. In multivariate analyses, older age (odds ratio = 1.063) and fever (odds ratio = 3.127) were associated with cytopenia.

CONCLUSIONS

Brucellosis is commonly presented with cytopenia, especially in bacteremic episodes with fever. However, pancytopenia is uncommon and its finding should alert the physician to look for other possible etiologies.

Performance of risk stratification criteria in the management of febrile young infants younger than three months of age

AIM

We evaluated the diagnosis, risk stratification and management of febrile infants under three months of age who presented to an Israeli paediatric emergency room (ER).

METHODS

This retrospective study enrolled all febrile infants examined in the paediatric ER of Soroka Medical Center during 2010-2013. The patients were classified into low-risk and high-risk subgroups and compared by age and ethnicity.

RESULTS

Overall, 2251 febrile infants (60.5% of Bedouin and 34.4% of Jewish ethnicity) were enrolled. Hospitalisation rates were higher among Bedouin vs. Jewish infants (55 vs. 39.8%, p < 0.001). Fever without localising signs was diagnosed in 1028 (45.6%) infants and 499 (48.5%) were hospitalised; 26% were stratified as high-risk and 74% as low-risk. Bedouin infants rates were more likely to be at high-risk (p = 0.001) and hospitalised (p < 0.001) than Jewish infants. With regard to low-risk infants, the incidence rates were higher before two months than two to three months of age (73.3 vs. 59%, p < 0.001), as were the hospitalisation rates (46.3 vs. 20.1%, p < 0.001). No differences were recorded for the hospitalisation rates of Bedouin and Jewish infants between the three daily shifts.

CONCLUSION

Major differences were recorded in hospitalisation rates, risk stratification and management of Bedouin and Jewish infants with fever without localising signs.

The Price of a Neglected Zoonosis: Case-Control Study to Estimate Healthcare Utilization Costs of Human Brucellosis

Human brucellosis has reemerged as a serious public health threat to the Bedouin population of southern Israel in recent years. Little is known about its economic implications derived from elevated healthcare utilization (HCU). Our objective was to estimate the HCU costs associated with human brucellosis from the insurer perspective. A case-control retrospective study was conducted among Clalit Health Services (CHS) enrollees. Brucellosis cases were defined as individuals that were diagnosed with brucellosis at the Clinical Microbiology Laboratory of Soroka University Medical Center in the 2010–2012 period (n = 470). Control subjects were randomly selected and matched 1:3 by age, sex, clinic, and primary physician (n = 1,410). HCU data, demographic characteristics and comorbidities were obtained from CHS computerized database. Mean±SD age of the brucellosis cases was 26.6±17.6 years. 63% were male and 85% were Bedouins. No significant difference in Charlson comorbidity index was found between brucellosis cases and controls (0.41 vs. 0.45, respectively, P = 0.391). Before diagnosis (baseline), the average total annual HCU cost of brucellosis cases was slightly yet significantly higher than that of the control group ($439 vs. $382, P<0.05), however, no significant differences were found at baseline in the predominant components of HCU, i.e. hospitalizations, diagnostic procedures, and medications. At the year following diagnosis, the average total annual HCU costs of brucellosis cases was significantly higher than that of controls ($1,327 vs. $380, respectively, P<0.001). Most of the difference stems from 7.9 times higher hospitalization costs (p<0.001). Additional elevated costs were 3.6 times higher laboratory tests (P<0.001), 2.8 times higher emergency room visits (P<0.001), 1.8 times higher medication (P<0.001) and 1.3 times higher diagnostic procedures (P<0.001). We conclude that human brucellosis is associated with elevated HCU costs. Considering these results in cost-effective analyses may be crucial for both reducing health inequities and optimal allocation of health systems’ scarce resources.

Epidemiological, diagnostic, clinical, and therapeutic aspects of Brucella bacteremia in children in southern Israel: a 7-year retrospective study (2005-2011)

BACKGROUND

Data on the various aspects of brucellosis in children living in southern Israel are missing.

OBJECTIVES

Our aim was to study the epidemiological, microbiological, diagnostic, clinical, therapeutic and outcome features of brucellosis in children <19 years of age in southern Israel during 2005-2011.

PATIENTS AND METHODS

The study population included all patients hospitalized with a diagnosis of brucellosis, established according to a clinical presentation compatible with brucellosis+presence of Brucella bacteremia (BB).

RESULTS

A total of 128 (50.8%) of 252 patients admitted with a diagnosis of brucellosis had BB (all with Brucella melitensis). All patients were of Muslim Bedouin ethnicity. The mean incidence of BB in southern Israel was 16 cases/100,000 Bedouin, with no significant changes during the study period. Overall duration of symptoms before diagnosis was 10.1±10.9 days. Fever at diagnosis was recorded in <20% of the patients. The most frequent symptoms were arthralgia (61.7%), weakness (32.8%), gastrointestinal disturbances (27.3%), myalgia (25%), and headache (18.8%). The main clinical findings included monoarthritis (36.7%), hepatosplenomegaly (25%), lymphadenopathy (17.2%), heart murmur (11.7%), and skin rash (9.4%), respectively. Anemia, leukopenia, thrombocytopenia, and pancytopenia were reported in 17.6%, 29.6%, 12.8%, and 2.3% of the patients, respectively. Twenty-nine (30.5%) patients with BB had serum agglutinin titers ≤1/160 (13, 13.7%%, had titers <1/160). Twenty-seven (93%) of the 29 patients aged 0-4 years were treated with gentamicin and trimethoprim-sulfamethoxazole; a total of 77 (60.2%) patients received gentamicin and doxycycline.

CONCLUSIONS

Childhood brucellosis remains an important public health problem in southern Israel. BB was diagnosed in >50% of the children with brucellosis, and B. melitensis was identified in all cases. Arthralgia, weakness, and gastrointestinal complaints were the most common symptoms, and monoarthritis, hepatosplenomegaly, and lymphadenopathy were the most common clinical findings. A considerable number of patients with BB had undetectable/low serum agglutinin titers, suggesting insufficient reliability on serology alone in diagnosis of brucellosis.

Community-acquired bloodstream infections in children > one month old in southern Israel (1992–2001): Epidemiological, clinical and microbiological aspects

We studied the epidemiology, microbiology, clinical picture and outcome of community-acquired bloodstream infections (CABI) in children in southern Israel during 1992-2001. Information was collected prospectively by daily surveillance. CABI was diagnosed when a positive blood culture was reported in a patient discharged from the emergency room or during <48 h since admission if hospitalized. There were 1439 CABI episodes in 1396 children aged 1 month to 14 y. CABI incidence was 100/100,000 children with no increase during the study period. Risk of CABI was 3.8 times higher in a Bedouin than in a Jewish child. 1561 bacteria (793, 50%, gram-positive and 768, 49% gram-negative organisms, respectively) and 13 fungi were recovered. Most frequent gram-positive organisms were Streptococcus pneumoniae (509 isolates, 32% of all isolates, 64% of all gram-positive), Staphylococcus aureus (137, 9%, 17%) and Streptococcus pyogenes (46, 3%, 6%). Enterobacteriaceae spp. were the most frequent gram-negative pathogens (279, 18%, 36%), followed by Brucella (205, 13%, 27%). S. pneumoniae was the most common pathogen in children <12 months and 1-5 y age; Brucella was the most frequent pathogen in children >5 y of age. Coverage of 7-valent pneumococcal conjugated vaccine for CABI was 38.5%. 38 (2.7%) patients died; 16 cases were caused by S. pneumoniae.

Murine typhus is a common cause of febrile illness in Bedouin children in Israel

Murine typhus is known to be endemic among populations living in poverty and exposed to rats and their fleas. A prospective 2-y study was conducted to determine the contribution of murine typhus to undifferentiated febrile illnesses among Bedouin children attending an outpatient clinic in southern Israel. Children with fever > or = 38.5 degrees C lasting for > or = 3 d were enrolled in the study. Murine typhus was serologically confirmed by the microimmunofluorescence test. A total of 549 children met the inclusion criteria of whom 76 (13.8%) had serologically-confirmed murine typhus. The disease was diagnosed in 27 of 434 (6.2%) patients aged < 5 y and in 49 of 115 (42.6%) older children (p<0.001). Murine typhus was diagnosed in 54 of 288 (18.8%) patients between June and November and in 22 of 261 (8.4%) between December and May (p<0.001). Patients with murine typhus had significantly higher prevalence of anaemia, leukopenia, hyponatraemia, and elevated liver enzymes compared to children without the disease. A single child was hospitalized and all 76 patients recovered without complications. Murine typhus is an important cause of febrile illnesses among Bedouin children > or = 5 y of age living in southern Israel and usually runs a benign clinical course.