วันพุธที่ 22 กุมภาพันธ์ พ.ศ. 2555

ไข้ในทารกแรกเกิด

Fever in the infant and toddler is one of the most common problems and greatest challenges faced by those caring for them

Neonates

Neonates with fever who are aged 28 days or younger may have few clues on history and physical examination to guide therapy. Therefore, a high index of suspicion is necessary in order to detect the febrile neonate with a serious bacterial infection. Obtaining the pertinent medical history from the mother regarding the pregnancy, delivery, and early neonatal life of the febrile neonate is essential. Typically, infections that occur in the first week of life are secondary to vertical transmission, and those infections occurring after the first week are usually community acquired or hospital acquired.

Definitive identification of a serious bacterial infection requires laboratory investigation; a full sepsis evaluation; and a positive result in blood culture, cerebrospinal fluid (CSF), and/or urine. Bacterial meningitis is more common in the first month of life than at any other time. An estimated 5-10% of neonates with early onset group B streptococcal (GBS) sepsis have concurrent meningitis.[1]

Prenatal history

A review of the prenatal history, including maternal history of sexually transmitted infections (human immunodeficiency virus [HIV], hepatitis B and hepatitis C, syphilis, gonorrhea, chlamydia, herpes simplex), maternal group B Streptococcus (GBS) status and prophylaxis, mode of delivery, prolonged rupture of membranes, and history of maternal fever should be noted.

A birth weight of less than 2500 g, rupture of membranes before the onset of labor, septic or traumatic delivery, fetal hypoxia, maternal peripartum infection, and galactosemia are all risk factors for a serious bacterial infection in the neonate. Gestational age should be determined, because premature infants are at increased risk for serious bacterial infections.

Nursery course

The neonate’s nursery course should be noted, including the age at which the patient went home from the nursery, whether or not a male neonate has been circumcised, and the use of peripartum or antepartum antibiotics. Any underlying diseases or conditions, as well as the use of medications that may increase the risk of infection, should be ascertained. Diet (ie, quantity and description of milk consumed; breast milk vs formula; and, if pertinent, the method the caregiver uses for preparing and storing the formula) and sleep histories should be obtained, because decreased oral intake or an acute change in sleep patterns may be clues to an invasive infection.

Household contacts

Any ill contacts in the household should also be noted. Exposure to any animals inside the home of the caregiver or outside the home (eg, in daycare facility) should be determined. The vaccination status of household members should be determined. A history of maternal fetal loss or death due to an infectious disease in a previous infant increases the suspicion of congenital anomalies and primary immunodeficiencies.

Identifying who is in the neonate’s household, who is the primary caregiver, contact with recent immigrants, and exposure to homelessness and poverty all impact the care the neonate receives.

Review of systems and physical examination

A thorough review of systems must be obtained to identify any other symptoms associated with the fever. A complete physical examination including vital signs (temperature 38°C = 100.4°F), pulse oximetry, and growth parameters with percentiles is necessary. General appearance should be noted for activity level, color, tone, and irritability. Signs of localized infection should be identified via a thorough examination of the skin, mucous membrane, ear, and extremities.

The presence of an umbilical stump after age 4 weeks should be noted, because it is a potential clue to leukocyte adhesion deficiency, and the lack of a circumcision in males should be noted, because it increases the risk for a urinary tract infection (UTI). In addition to fever, the most common clinical features of a UTI in a neonate include failure to thrive, jaundice (typically secondary to conjugated hyperbilirubinemia from cholestasis), and vomiting. Irritability, inconsolability, poor perfusion, poor tone, decreased activity, and lethargy can be signs of a serious infection in this age group.

Most neonates with bacterial meningitis have a full fontanelle with normal neck flexion at the time of presentation. Remember that neonates younger than 28 days with significant bacterial infections can appear to be at low risk when analyzing history, physical examination findings, and laboratory values; thus, a high index of suspicion must be maintained.

Diagnostic Considerations

Clinicians must maintain a high index of suspicion for serious bacterial and/or viral infections in febrile infants and toddlers. The diagnostic approach consists of a targeted medical history, a complete physical examination, and the judicious use of the laboratory tests.

Differentials

  • Bacteremia
  • Neonatal Sepsis
  • Pediatric Bacterial Meningitis
  • Pediatric Escherichia Coli Infections
  • Pediatric Haemophilus Influenzae Infection
  • Pediatric Meningitis and Encephalitis
  • Pediatric Pneumococcal Bacteremia
  • Pediatric Urinary Tract Infection
  • Staphylococcus Aureus Infection
  • Streptococcus Group B Infections

    Approach Considerations

    The clinical management of infants and toddlers with fever is based on their age groups.

    Neonates and young infants should be hospitalized with intravenous antibiotics pending results of laboratory tests and cultures.

    For the most part, management should be individualized based on risk factors, clinical appearance, and clinical judgment. Ill-appearing children with poor capillary refill and children who have clinical signs and symptoms suggestive of meningitis need to be managed in hospital and perhaps in the critical care setting. Children with focal infections such as sinusitis and pneumonia need to be managed with appropriate antimicrobial therapy.

    With the widespread use of pneumococcal vaccine in young children, the incidence of occult bacteremia in febrile children aged 3 months to 3 years has fallen from 4.6% to less than 1%.[5, 16] As such, the evaluation has become more extensive to prevent overtreatment. In the absence of focal findings, any child in the target age group who appears ill or has excessive fever, vomiting, or tachypnea with retractions should be evaluated further.

    Parents and medical professionals who want to supplement physical measures with medication in order to maximize the time that children spend without fever should use ibuprofen first and weigh the use of paracetamol plus ibuprofen over 24 hours.[17]

  • Medication Summary

    Antibiotics are used to treat occult bacterial infection. Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens for the patient's age range and in the clinical setting. Whenever feasible, select antibiotics based upon blood culture sensitivity.

ไม่มีความคิดเห็น:

แสดงความคิดเห็น