Is That Conjunctivitis Bacterial or Viral?|
In general, about a half of pediatric conjunctivitis is caused by bacteria and half by viruses. Differentiating the two without getting a culture can be difficult. Most textbooks and studies offering clinical criteria to distinguish these etiologies do not offer the data to back them up. A recent study attempted to identify children 6 months - 17 years old (median 3 years) at low risk for bacterial conjunctivitis based on clinical findings. Positive cultures, seen in 64.7%, grew Haemophilus influenzae
(67.6%), pneumococcus (19.7%), Staphylococcus aureus
(8%), and H. parainfluenzae
(2.5%). They identified 4 predictors that increased the chance of getting a negative culture: 1) age >6 y, 2) presentation in April-November, 3) no or watery discharge, & 4) no glued eye in the morning. The table below shows the probability that a child's culture will be negative based is upon the number of predictors present. Few children with 4 predictors will have a bacterial infection.
# of predictors
Probability of a negative culture, %
Although most children with conjunctivitis will still need treatment with topical antibiotics, this prediction model may make it easier to select those patients likely to have a viral infection and not need antibiotics.
Meltzer JA, et al. Arch Pediatri Adol Med 2010;164(3):263-7
Prophylactic Penicillin for Sickle Cell Patients|
A recent study revealed that Medicaid infants in Tennessee have poor compliance with receiving penicillin prophylaxis by 3 months of age, as recommended in a guideline. Only 40% had a prescription filled by 3 months of age. Risk of nonadherence rose with increasing number of the following risk factors: maternal age, marital status, education,income, and residence in an urban area. The study was not designed to identify whether prescriptions had been written by primary care providers. The NIH guideline "Management of Sickle Cell Disease" suggests that infants identified to have sickle cell disease on neonatal screening should be placed on penicillin prophylaxis "as early as possible." The recommended regimen is 125 mg PO BID for neonates to children 3 years old, and 250 mg PO BID for 3-5 years old. An alternative regimen is 1.2 million units of Bicillin IM every 3 weeks. Remember to give these kids the full schedule of conjugated pneumococcal vaccines (Prevnar), as well as a dose of polysaccharide pneumococcal vaccine (Pneumovax) at 2 years of age and a booster dose 5 years later.|
Warren MD, et al. Arch Pediatr Adol Med 2010;164(3):298-9.
NIH publication #02-2117. The Management of Sickle Cell Disease, 2002.
HSP triggered by Helicobacter pylori|
|Henoch-Schonlein purpura (HSP) is a vasculitis with a typical clinical presentation of a palpable, purpuric rash that is most prominent on posterior legs and buttocks, and can involve the face and extensor surfaces of the arms. Many children with HSP have had a preceding respiratory or gastrointestinal illness. A few reports have suggested that H. pylori may sometimes trigger HSP. One case report of a child with H. Pylori infection demonstrated the deposition of IgA and C3 complement in dermal blood vessel walls. Others reports have shown that patients with H. pylori infection have elevated levels of serum IgA, lower levels of C3 complement, and more frequent increases of circulating immune complexes and cryoglobulin. Increased serum IgA and decreased C3 levels have also been reported in some patients with HSP. Perhaps, in some patients, H. pylori can cause an aberrant immune response resulting in HSP. In the case report cited below (which case report?), the child's HSP symptoms resolved after starting therapy for H. pylori.|
Mytinger JR, et al. Ped Derm 2008;25(6):630-2.
Shin JI, et al. Ped Derm 2009;26(6):768-9.
Take Part in Our Vaccine Survey
A Message from David Berman, D.O.
Pediatric Infectious Disease Program
All Children's Specialty Physician
|All physicians are encouraged to complete the brief survey regardless of your opinion regarding
childhood vaccination. If enough responses are received, the anonymous results will
be presented at the Annual Suncoast Pediatric Conference (Sarasota, Florida) in
Thank you for your participation.
Once-Daily Dosing (ODD) of Gentamicin|
The aminoglycoside antibiotics are often employed in the treatment of Gram-negative infections. A standard dosing regimen has been to divide the total daily dose into 3 doses given every 8 hours. The last 20 years has seen increasing interest in ODD of aminoglycosides, first in adults and subsequently in children. Such dosing has the potential to increase antibacterial activity and decrease nephrotoxicity. Although the dosing standards have been developed for adults, the published data on ideal doses in children has been less clear. In a recent pharmacokinetic study in children without cystic fibrosis over 3 months of age, investigators extrapolated the following once-daily doses to achieve peak gentamicin serum levels of >20 mcg/ml:|
3 month to <2 years
2 to <8 years
Such dosing may not be applicable to patients with renal insufficiency. Further studies will have to be done to confirm these results and to establish safety and efficacy.
McDade EJ, et al. Pharmacotherapy 2010;30(3):248-53.
Evaluation of Inpatient
Admissions and Potential Antimicrobial and Analgesic Errors in Overweight
The prevalence of overweight and
obesity in American children has increased steadily over the last several
decades. The Centers for Disease Control and Prevention (CDC) and Institutes of
Medicine recognize children as overweight and obese if their body mass index
(BMI) exceeds the 85th and 95% percentile, respectively. A
retrospective study of children aged 5-12 years who were admitted to a
children's hospital over a period of 6 months was conducted to determine the
percentage of admissions of children with a BMI greater than or equal to the 85th
percentile for age and sex and the mean error rate per admission in the
overweight versus control group.|
A total of 839 admissions
representing 699 patients were included. The overweight group included 278
(33.1%) admissions. Comparison of overall mean error rate per admission
revealed a statistically significant increase in dosing errors for overweight
patents (0.4 ± 0.6 vs. 0.3 ± 0.6; p=0.030), with underdose errors
occurring more frequently than overdose errors (0.3 ± 0.6 vs. 0.5;
p=0.010). The antimicrobial agents associated with the most risk of underdosing
in the overweight group included cefazolin, ceftriaxone, vancomycin,
amoxicillin and cefpodoxime, The antimicrobial agents associated with the most
risk of overdosing in the overweight group included gentamicin, tobramycin and
In this study, overweight children accounted for
one-third of admissions and appeared to be at greater risk for dosing errors,
specifically for under- and overdosing of antimicrobials. This study did not
focus on clinical outcomes of under- or overdosing; however, clinicians should be
aware that overweight and obese children could be at an increased risk for
therapeutic failures or adverse effects. Strategies to decrease potential
dosing errors in overweight children include providing an assessment in
children who weigh 40kg or more - the clinician should assess whether or not
weight-based dosing is appropriate for that specific medication and indication.
Secondly, clinicians should be familiar with adult dosing recommendations so as
not to exceed, maximum adult doses.
Miller JL, Johnson, PN, Harrision, DL et al. Annals of Pharmacotherapy.2010; 44:35-42
Can Deer Ticks Transmit Bartonella henselae?|
Bacteria of the genus Bartonella, which encompasses over 20 different species, is responsible for a large variety of animal and human infections. Recently, several studies have demonstrated Bartonella spp. DNA by PCR in ticks.
Because of these findings, some healthcare providers believe that B. henselae is present in and, therefore, transmissible, by the deer tick (Ixodes scapularis). In addition, there is also a concern that coinfection of Borrelia burgdorferi, the causative agent of Lyme disease and Bartonella henselae, the causative agent of cat scratch disease may occur.
A list reasons why deer ticks are unlikely or not proven to be responsible for transmission of Bartonella henselae is as follows:
- Typical cat-scratch disease after a recognized deer tick bite has not been observed.
- There is an absence of reports of typical lymph node findings of cat-scratch disease proximal to the bite tick.
- Cat-scratch disease has a different seasonal pattern from that of Lyme disease.
- The seasonality of cat-scratch disease, in (most cases in temperate regions occur in autumn and early winter when peak breeding of cat fleas and birth of kittens occur) is different than the seasonality for Lyme disease (which occurs predominantly in summer with some cases in spring and autumn).
- Appropriate seroepidemiologic studies have not been done.
- Vector competence of ticks for B. henselae in an animal system has not been proven.
- No convincing evidence of B. henselae in deer ticks has been reported.
- The Bartonella species present in Peromyscus leucopus (the white-footed mouse) is not B. henselae.
- The US cases with convincing evidence of B. henselae infection after a tick bite occurred in areas where Lyme disease is not endemic
Another important point to consider is that the presence of a microbial agent within a tick does not imply that the tick might transmit it during the course of blood feeding and does not confer epidemiologic importance.
In summary, there is insufficient evidence for tick transmission of any Bartonella spp. to humans and there are no published well-documented cases of B. henselae transmission by I. scapularis ticks.
Sam R. Telford III and Gary P. Wormser. Bartonella spp. Transmission by Ticks Not Established Emerging Infectious Diseases · Vol. 16, No. 3, March 2010
Tuberculosis (TB) Facts in the US and Florida and the TB
Genotyping Information Management System|
U.S. TB facts
In 2008, 12,904 TB cases (a rate of
4.2 cases per 100,000 persons) were reported in the United States representing
a 2.9% decline in the number of TB cases and a 3.8% declining TB case rate
compared to 2007. Of note, California, Texas, New York, and Florida accounted
for 49% of the national TB case total.
is a substantial TB burden among the foreign-born. The percentage of cases
occurring in foreign-born persons has continued to increase and was 59% of the
national case total. The top five
countries of origin of foreign-born persons with TB were Mexico, Philippines,
Vietnam, India and China.
highest burden of TB disease continues to be among older adults. In 2008,
adults aged 65 years and older had a case rate of 6.4 cases per 100,000. Children aged <14 years had the lowest
rate at 1.3 cases per 100,000.
proportion of patients with primary multidrug-resistant TB (MDR TB), which is
defined as no previous history of TB disease and resistance to at least isoniazid
and rifampin, has decreased from 2.5% to 1.0% in 2008. However, the proportion of primary MDR TB
cases occurring in foreign-born persons increased from 25.3% (103 of 407) in
1993 to 76.7% (66 of 86) in 2008.
drug-resistant TB (XDR TB) is defined as resistance to isoniazid and rifampin
plus resistance to any fluoroquinolone and at least one of three inject-able
second-line anti-TB drugs (i.e., amikacin, kanamycin, or capreomycin). Four
cases of XDR TB were reported during 2008, compared to two cases in 2007.
Florida TB facts
2007 and 2008, Florida reported 988 and 954 cases of TB to the CDC,
respectively. The rates of TB cases per
100,000 persons for 2007 and 2008 were 5.4 and 5.2, respectively. In 2008, Florida ranked 6th in the
nation with regards to the number of TB cases. Children under 5 years of age accounted for 4% of cases while children
ages 5-14 years of age accounted for 0.9% of cases.
In order to accurately track cases of TB and halt the
spread of TB, CDC has begun a program that enables TB genotyping on all isolates and
links all related cases to help monitor progress in eliminating TB. TB genotyping is a laboratory-based approach
used to analyze Mycobacterium tuberculosis DNA. Specific sections of the M. tuberculosis
genome form distinct genetic patterns that help distinguish different strains
of M. tuberculosis. The CDC's
program is The TB Genotyping Information Management System (TB GIMS), and is a secure
web-based system designed to improve access and dissemination of the TB
genotyping information nationwide. TB GIMS was released in March 2010. This program is truly an advancement in the
control of TB in the U.S. and will help monitor the progress in eliminating TB
in the U.S.
CDC. TB Genotyping Information
Management System (TB GIMS). Factsheet, 2009. Available at http://www.cdc.gov/tb/publications/factsheets/statistics/tbgims.pdf . Accessed March 11, 2010.
CDC. New CDC program for rapid genotyping of Mycobacterium tuberculosis isolates. MMWR 2005;54:47.
Screening Newborns for Congenital CMV Infection|
Cytomegalovirus (CMV) infection is now the most common congenital viral infection. The prevalence of sensorineural hearing loss among newborns with symptomatic CMV disease is 30-50%. Even in infants with "silent CMV infection", sensorineural hearing loss occurs in 6-8%. Many CMV-infected infants may have normal hearing at birth and develop hearing loss later. Fourteen years ago, investigators first detected CMV DNA in newborn dried blood spots (DBS) among infants with congenital CMV. |
In a recently published study, investigators wanted to determine the accuracy of polymerase chain reaction detecting CMV DNA from DBS as a screening test in newborns. This multicenter study was carried out at seven medical centers over a 14-month period during 2007-2008. Results from salivary culture were compared to PCR.
Congenital CMV was diagnosed in 92 (91 of 92 had positive results on salivary culture) of 20,448 tested (0.45%). Using a single-primer DBS PCR, CMV DNA was only detected from 17 of 60 (28%). Using a 2-primer DBS PCR, CMV DNA was only detected from 11 of 32 (34%). Compared to rapid salivary culture, the DBS PCR had very low sensitivity.
This large multi-center trial demonstrated that using DBS PCR has limited value as a screening test due to the low sensitivity. One future approach for screening with better sensitivity would be salivary testing in infants since most CMV-infected infants have DNA in the saliva.
JAMA 2010;303 (14):1375-1382
JAMA 2010;303 (14):1425-1426
|David M. Berman, D.O.|
Juan Dumois III, M.D.
Shirley Jankelevich, M.D.
Allison Messina, M.D.
Dale Bergamo, M.D.
Patricia Emmanuel, M.D.
Jorge Lujan-Zilbermann, M.D.
Carina A. Rodriguez, M.D.
Katie Namtu, Pharm.D.
All Children's Hospital
Tampa General Hospital
Bayfront Baby Place
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