Response of preterm infants to diphtheria-tetanus-pertussis immunizations

To establish guidelines for the routine use of diphtheria, tetanus, and pertussis (DTP) vaccine in preterm infants, we quantitated antibody responses of preterm infants to DTP and determined the nature and extent of side effects. Twenty-five preterm infants were immunized with 0.5 ml DTP vaccine at routine intervals. Term infants served as controls. Immediately before each immunization and 2 months after the third, DTP-specific antibodies were quantitated. Clinical side effects were determined by parental report. After the second immunization, 100% of preterm infants had evidence of specific antibody production against diphtheria, tetanus, and pertussis. The incidence of side effects was low, but irritability was significantly more common in preterm infants after the second immunization. These observations suggest that the initiation of primary immunization with DTP in preterm infants need not be delayed beyond 2 months of age.     

Language development survey provides a useful screening tool for language delay in preterm infants

Developmental language disorder has been reported in 3% to 10% of term infants and 30% of preterm infants (<34 weeks gestation). Screening for language delay in preterm infants can be costly and time-consuming. The objective of this study was to assess the expressive language development of preterm infants using the Language Development Survey (LDS). A total of 178 preterm infants born at 23 to 34 weeks between 2006 and 2008 were enrolled. The LDS was completed by parents between 22 and 26 months at or shortly before 2-year neurodevelopmental assessment using the Bayley III Scale. A total of 26% of former preterm patients had language delay, using LDS. Significant correlations were observed between LDS results and Bayley III scores. Male gender and public health insurance were the most important risk factors for language delay in this cohort. Expressive language delay was present in 26% of preterm infants. LDS is a suitable and inexpensive screening tool for assessing language delay in preterm infants.     

Immunogenicity and immunologic memory of meningococcal C conjugate vaccine in premature infants

BACKGROUND: Protein-polysaccharide conjugate vaccines against Neisseria meningitidis serogroup C were introduced into the U.K. routine immunization schedule in 1999. This study is the first to describe both persistence of antibody and evidence for induction of immune memory using meningococcal C conjugate (MCC) vaccine in preterm infants. METHODS: Immunogenicity and induction of immunologic memory by as MCC vaccine was assessed in premature infants; 62 preterm and 60 term controls received MCC at the accelerated schedule (2, 3 and 4 months of age). A meningococcal C polysaccharide challenge was administered at 12 months of age. RESULTS: Both groups achieved similar protective titers after primary immunization that then waned significantly by 1 year of age. Postchallenge serum bactericidal activity was significantly lower in preterm infants (P = 0.03); 73% of preterm versus 88% of term controls achieved a 4-fold rise in serum bactericidal activity (P = 0.07). CONCLUSIONS: MCC vaccine is immunogenic and primes for immunologic memory in preterm infants. The decreased memory responses in these preterm infants in conjunction with waning clinical efficacy data for all U.K. infants suggest a role for a routine booster dose of vaccine in all infants receiving MCC, especially those born preterm.     

Adverse reactions to immunization with newer vaccines in the very preterm infant

OBJECTIVE: To study the frequency and types of adverse reactions to currently available vaccines in very preterm infants. METHODS: Case notes were obtained for very preterm infants < or =30 weeks' gestational age who received their first immunization at the Royal Women's Hospital, Melbourne, during 1999-2003. Data were extracted for the time periods 48 h before and 48 h after immunizations, with the data extraction blinded as to whether the period being evaluated was pre- or post-immunization. Data collected focused on the frequency and severity of apnoea, respiratory support, fever and clinical consequences of adverse reactions. RESULTS: A total of 48 very preterm infants were immunized during the period; 37 infants had Comvax (Haemophilus influenzae type B and hepatitis B vaccine), Infanrix (diphtheria, tetanus and acellular pertussis vaccine) and inactivated poliomyelitis vaccine, and 11 infants had Comvax and Infanrix only. Their mean (SD) gestational age at birth was 26.4 (1.7) weeks with mean birthweight of 872 (235) g. The mean postnatal age at immunization was 76 (20) days. Low-grade fever (>37.5 degrees C per axilla) occurred in 16 (33%) infants after immunization, but none before immunization (P < 0.001). There was no substantial change in recorded apnoea. No serious adverse events were noted. Four (8%) infants underwent a septic work up post-immunization. The C-reactive protein was increased in all four infants, but other tests for sepsis were negative. CONCLUSION: Fever remains a common adverse event following immunization of the preterm infant in spite of the development of a new generation of vaccines.     

Incidence of apnoea and bradycardia in preterm infants following DTPw and Hib immunization: A prospective study

Objective: To evaluate the incidence and severity of apnoea and bradycardia in hospitalized preterm infants following immunization at 2 months of age, and identify risk factors.
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTP_w) in the neonatal intensive care unit (NICU) at King George V Hospital Sydney. Half the infants also received Haemophilus influenzae type b conjugate vaccine (Hib) simultaneously. All infants were monitored for apnoea and bradycardia in the 24 h periods pre- and post immunization.
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTP_w were less likely to have apnoea and/or bradycardia than those given DTP_w alone.
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization.     

晚期早产儿和早期足月儿1岁时神经心理发育水平的随访研究

目的 探讨晚期早产儿和早期足月儿1岁时的神经心理发育水平。方法 选择矫正年龄为1岁的1 257名儿童为研究对象。根据其出生时胎龄分为4组：早期早产儿（胎龄28~33⁺⁶周）、晚期早产儿（胎龄34~36⁺⁶周）、早期足月儿（胎龄37~38⁺⁶周）及完全足月儿（胎龄39~41⁺⁶周）。采用Gesell发展量表评估其神经心理发育水平,比较各组儿童在1岁时神经心理发育状况。结果 4组儿童1岁时5大能区（适应性、大运动、精细动作、语言、个人社交）发育商的差异均有统计学意义（P < 0.05）,且均表现为完全足月儿 > 早期足月儿 > 晚期早产儿 > 早期早产儿的趋势（P < 0.05）;各能区发育迟缓率也均表现为完全足月儿最低,早期早产儿最高（P < 0.05）。与完全足月儿相比,早期足月儿适应能力发育落后的风险增加（OR=1.796,P < 0.05）;晚期早产儿适应能力和精细动作发育落后的风险较高,OR值分别为2.651、2.679（P < 0.05）;早期早产儿适应能力、精细动作和个人社交能力发育落后的风险较高,OR值分别为4.069、3.710、3.515（P < 0.05）。结论 儿童1岁时神经心理发育落后的风险随出生胎龄的增加而降低,呈现剂量反应效应。早期足月儿和晚期早产儿仍然存在不同程度的发育落后,应重视早期足月儿和晚期早产儿的保健随访。     

Incidence of apnoea and bradycardia in preterm infants following triple antigen immunization

Ninety-seven preterm infants were immunized with diphtheria-tetanus-pertussis (DTP) prior to discharge from hospital. The mean gestational age at birth was 28.1 weeks (range 24-34) and the mean age at immunization was 80.6 days (range 44–257). Nineteen (20%) infants developed apnoea or bradycardia within 24 h of immunization. The infants who developed apnoea and/or bradycardia had a younger gestational age at birth than those who did not (P= 0.03), were artificially ventilated for longer (P= 0.01) and were more likely to have a diagnosis of chronic lung disease (P= 0.006). In the majority of infants these events were not clinically significant. Two infants who developed concurrent upper respiratory tract infections required additional oxygen and one of them was treated with oral theophylline. In general, it is safe practice to immunize preterm infants with DTP unless otherwise contraindicated. However, it is recommended that cardiorespiratory function is monitored after immunization in very preterm infants who had prolonged ventilatory support and/or chronic lung disease.     

Developmental outcome of very preterm babies using an assessment tool deliverable by health visitors

AimTo assess the developmental outcome of very preterm infants using a developmental screening tool deliverable by health visitors.MethodsThe study cohort consisted of preterm infants born at <32 weeks gestation or <1500 g. Infants were assessed at 12 and 24 months corrected age using the Schedule of Growing Skills developmental screening test. Scores for skill areas were converted to developmental levels in months and graded as normal or mild, moderate or severe delay.ResultsOf 101 infants assessed at 12 months, 12 (12%) had severe developmental delay (developmental level <6months) in one or more skill areas. At 24 months, severe developmental delay (developmental level <12 months) was found in 8 (9.1%) infants. Only 3 infants had severe global delay. However, approximately a third of infants showed mild or moderate delay in hearing and language, social or cognitive skill areas by 24 months.ConclusionDevelopmental assessment undertaken by health visitors may be used to measure outcome in preterm infants. Severe developmental delay was at a level consistent with other follow-up studies of very preterm infants. Severe delay was identified by the 12-month check and was mainly in areas of motor function and language. High levels of mild to moderate developmental delay were identified at the 24-month assessment.     

Response of preterm infants to diphtheria-tetanus-pertussis vaccine

The American Academy of Pediatrics recommendation that immunization of preterm infants with diphtheria-tetanus-pertussis (DTP) vaccine should begin at 2 months after birth, regardless of gestational age, is based on limited data. A prospective study was conducted to determine the immunogenicity and safety of DTP vaccine in preterm infants. One hundred ten preterm and 146 full term infants received doses of DTP at 2, 4 and 6 months after birth. Adjusted analysis of the antibody responses indicated that after three doses mean titers among preterm infants to each vaccine component were comparable to those of full term infants. Adjusted analysis of the incidence of adverse events indicated that the risk of adverse events in preterm infants was not significantly higher than that in full term infants. DTP vaccine is immunogenic and safe in preterm infants when the series is initiated at 2 months after birth, and this study supports the current recommendation of the American Academy of Pediatrics.     

单胎濒死儿发生的围生期危险因素分析（英文翻译）

目的 研究早产儿校正18~24月龄时的体格生长和神经发育水平。 方法 利用早产儿出院后随访系统,前瞻性收集2018年4月—2021年12月在暨南大学附属深圳市宝安区妇幼保健院定期随访的484例早产儿校正18~24月龄的体格生长数据和神经发育评估数据。219例足月儿作为对照。采用儿童神经心理行为检查量表2016版评估神经发育水平。根据胎龄分组（超早产儿组、极早产儿组、中期早产儿组、晚期早产儿组和足月儿组）,比较各组体格生长和神经发育水平。 结果 除中期早产儿组年龄别身长Z值高于足月儿组（P=0.038）,其余各早产儿组的体格生长指标与足月儿组比较差异均无统计学意义（均P>0.05）。各早产儿组总发育商（developmental quotient,DQ）均低于足月儿组（均P<0.05）;除社会行为能区外,超、极早产儿组其他各能区DQ均低于足月儿组（均P<0.05）;胎龄<32周早产儿全面发育迟缓发生率（16.7%）显著高于足月儿组（6.4%）（P=0.012）,全面发育迟缓发生率有随着胎龄减小而升高的趋势（P=0.026）。 结论 早产儿校正18~24月龄时体格生长可完成追赶,但神经发育水平落后于足月儿,应特别重视胎龄<32周早产儿的神经发育监测及早期干预。     

晚期早产儿脑损伤的常见发病因素

晚期早产儿又称近足月儿.该胎龄的早产儿外表接近成熟,由于器官发育不成熟,比足月儿存在更大发病风险,脑损伤与足月儿相比发病风险明显增加,脑性瘫痪的发病率增加3倍,生长发育/心理发育迟缓也有明显增多,这主要与晚期早产儿脑发育不成熟有关.晚期早产儿其他系统的常见病发生率也比较高,如窒息、低血糖、高胆红素血症、呼吸窘迫综合征、...     

Gross motor milestones in preterm infants: correction for degree of prematurity

The age of gross motor milestone attainment and how it is affected by degree of prematurity at delivery were studied in 100 high-risk, preterm (less than 32 weeks) infants with normal motor outcome. We calculated the mean age of attainment for each milestone on the basis of chronologic age from the date of delivery and term age equivalent, correcting for degree of preterm delivery. Half of these preterm infants were male; 70% were black. The infants were compared with a population of normal infants born at term. In this very preterm population, there were no consistent sex differences, but black infants generally attained motor milestones before white infants. For each motor milestone, regardless of gender or race, the mean term age equivalents of attainment for very preterm infants closely approximated the mean ages of milestone attainment for term infants, whereas the mean chronologic ages were delayed 2 or 3 months. We conclude that very preterm infants can be expected to demonstrate sequential gross motor development at a rate expected for degree of prematurity. Chronologic age is not a valid measurement scale to use in determining motor delay in very preterm infants.     

早产儿喂养不耐受临床诊疗指南（2020）

早产儿喂养不耐受是目前新生儿最常见的临床问题之一,常导致达全肠内营养时间延迟,住院时间延长。防治早产儿喂养不耐受对提高早产儿存活率有重要意义。该指南基于目前国内外研究,采用证据推荐分级的评估、制定与评价方法（GRADE）进行证据分级制定早产儿喂养不耐受的临床诊疗指南,旨在帮助新生儿科医生、护理人员、营养治疗师等对早产儿喂养不耐受进行早期识别与规范管理。     

Development of cystic periventricular leukomalacia in newborn infants after rotavirus infection

We describe 5 preterm and 3 term infants who presented with seizures during rotavirus infection within 6 weeks after birth. Six of these infants developed late-onset cystic periventricular leukomalacia. Four of the preterm infants had neurodevelopmental delay, and 4 (near) term infants had normal early outcome.     

Late preterm births: New insights from neonatal neuroimaging and neurobehaviour

With increasing evidence of neurodevelopmental problems faced by late preterm children, there is a need to explore possible underlying brain structural changes. The use of brain magnetic resonance imaging has provided insights of smaller and less mature brains in infants born late preterm, associated with developmental delay at 2 years. Another useful tool in the newborn period is neurobehavioural assessment, which has also been shown to be suboptimal in late preterm infants compared with tern infants. Suboptimal neurobehaviour is also associated with poorer 2-year neurodevelopment in late preterm infants. More research into these tools will provide a better understanding of the underlying processes of developmental deficits of late preterm children. The value of their role in clinical care remains to be determined.     

早产儿喂养不耐受临床诊疗指南（2020）

早产儿喂养不耐受是目前新生儿最常见的临床问题之一,常导致达全肠内营养时间延迟,住院时间延长。防治早产儿喂养不耐受对提高早产儿存活率有重要意义。该指南基于目前国内外研究,采用证据推荐分级的评估、制定与评价方法（GRADE）进行证据分级制定早产儿喂养不耐受的临床诊疗指南,旨在帮助新生儿科医生、护理人员、营养治疗师等对早产儿喂养不耐受进行早期识别与规范管理。     

Recurrence of cardiorespiratory events following repeat DTaP-based combined immunization in very low birth weight premature infants

We evaluated the tolerance to immunization of 64 very low birth weight preterm infants. Thirty-three of the infants experienced a cardiorespiratory event after the first vaccination, and 6 of these 33 (18%) had a recurrence after the second vaccination, including 2 infants previously discharged to home. A cardiorespiratory event associated with the first vaccination was the sole risk factor for recurrence identified.     

Half-dose immunization for diphtheria, tetanus, pertussis: response of preterm infants

The American Academy of Pediatrics currently recommends administering full-dose diphtheria, tetanus, pertussis, (DTP) vaccine to preterm infants, beginning at 2 months' chronologic age. Many physicians, however, continue to administer DTP vaccine at a reduced dosage in an attempt to lessen side effects. This study was designed to quantitate the immune response of 20 preterm infants immunized with half-dose DTP vaccine and to determine the nature and extent of side effects. Control subjects were 25 preterm infants immunized with full-dose vaccine. Although 96% of infants who received a full dose were able to mount a serologic response to pertussis after a second dose of DTP, 45% of infants who received a half dose were unable to mount a similar immune response to pertussis even after a third dose of DTP and required a full-dose (fourth dose of DTP) vaccine to better ensure protection. Serologic responses to diphtheria and tetanus were similar in the two groups. The incidence of side effects in preterm infants receiving both full-dose and half-dose DTP was less than that seen in a full-term population. Thus, the physician caring for the preterm infant should adhere to the American Academy of Pediatrics' recommendation for the immunization of preterm infants and offer full-dose DTP vaccine at the routine time intervals of 2, 4, 6, and 15 or 18 months' chronologic age to ensure adequate protection.     

晚期早产儿神经发育预后及影响因素分析

目的探讨晚期早产儿在校正年龄1岁时的神经发育情况及其影响因素。方法采用首都儿科研究所修订的《0～6岁小儿神经心理发育量表》,对2008年4月至2009年4月于本院产科分娩的晚期早产儿及足月儿在校正年龄/生后年龄满1岁时进行智能发育测试,按照发育商(DQ)将晚期早产儿分为神经行为发育异常组(DQ<85)和正常组(DQ≥85),分析可能对神经发育产生影响的社会家庭因素和临床相关因素,应用Logistic回归分析筛选影响晚期早产儿神经发育的危险因素。结果晚期早产儿组165例,校正年龄1岁时神经行为发育异常9例(5.5%),对照组102例,1岁时神经行为发育异常3例(2.9%),两组差异有统计学意义(χ2=5.047,P<0.05)。1岁时晚期早产儿DQ低于足月儿[(93.8±7.5)分比(98.8±9.8)分,P<0.05],其大运动、精细动作、语言均落后于足月儿。极低出生体重(OR=2.175)、低血糖(OR=1.924)、母亲文化程度初中以下(OR=0.602)是影响晚期早产儿神经发育预后的危险因素(P<0.05)。结论晚期早产儿是发生不良神经预后的高危人群,与极低出生体重、低血糖、母亲文化水平低密切相关。     

晚期早产儿早期智能发育结局的研究

目的探讨晚期早产儿(LPI)早期智能发育结局。方法选择2012年1月至2015年1月新生儿病房收治的出生胎龄34~36+6周、治愈出院并定期规律随访的106例早产儿为晚期早产儿组;随机抽取同期120例健康足月儿(FPI)为对照组。对校正年龄40周的晚期早产儿及40周龄的足月儿进行新生儿神经行为测定(NBNA),晚期早产儿校正龄3、6、12月龄或者足月儿3、6、12月龄时采用Gesell发育量表进行评估。结果 LPI组NBNA评分低于37分,低于FTI组(P0.05)。校正龄3月龄时,LPI组大运动、精细运动、个人社交落后于FTI组(P0.05);校正龄6月龄时,LPI组适应性、大运动、精细运动落后于FTI组(P0.05);校正年龄12月龄时,LPI组适应性、大运动、个人社交测评明显低于FTI组(P0.05)。结论晚期早产儿早期智能发育迟缓,需加强神经发育监测。