Diagnosis and management of community-acquired pneumonia in children: South African Thoracic Society guidelines

BACKGROUND

Pneumonia remains a major cause of morbidity and mortality amongst South African children. More comprehensive immunisation regimens, strengthening of HIV programmes, improvement in socioeconomic conditions and new preventive strategies have impacted on the epidemiology of pneumonia. Furthermore, sensitive diagnostic tests and better sampling methods in young children improve aetiological diagnosis.

OBJECTIVES

To produce revised guidelines for pneumonia in South African children under 5 years of age.

METHODS

The Paediatric Assembly of the South African Thoracic Society and the National Institute for Communicable Diseases established seven expert subgroups to revise existing South African guidelines focusing on: (i) epidemiology; (ii) aetiology; (iii) diagnosis; (iv) antibiotic management and supportive therapy; (v) management in intensive care; (vi) prevention; and (vii) considerations in HIV-infected or HIVexposed, uninfected (HEU) children. Each subgroup reviewed the published evidence in their area; in the absence of evidence, expert opinion was accepted. Evidence was graded using the British Thoracic Society (BTS) grading system. Sections were synthesized into an overall guideline which underwent peer review and revision.

RECOMMENDATIONS

Recommendations include a diagnostic approach, investigations, management and preventive strategies. Specific recommendations for HIV infected and HEU children are provided.

VALIDATION

The guideline is based on available published evidence supplemented by the consensus opinion of SA paediatric experts. Recommendations are consistent with those in published international guidelines.

Guideline for the diagnosis, prevention and treatment of paediatric ventilator-associated pneumonia

OBJECTIVE

Ventilator-associated pneumonia (VAP) has been poorly studied in South Africa, but is likely to be a significant problem, with resulting increased morbidity and mortality in the paediatric intensive care unit population. This guideline is intended to review the evidence and recommendations for prevention and management of VAP in children and to provide, where possible, clear advice to aid the care of these children, to limit costly and unnecessary therapies and--importantly--limit inappropriate use of antimicrobial agents,

EVIDENCE

The Working Group was constituted. Literature on the aetiology, prevention and management of paediatric VAP is reviewed.

RECOMMENDATIONS

Evidence-based clinical practice guidelines are provided for VAP diagnosis and prevention in South Africa. In addition, the current status of antimicrobial use has been reviewed and clear recommendations are set out.

Managing HIV in the PICU--the experience at the Red Cross War Memorial Children's Hospital in Cape Town

The HIV pandemic has affected children throughout the developing world. This article describes the experience of the Paediatric Intensive Care Unit at the Red Cross War Memorial Children's Hospital in Cape Town, South Africa. Over the last 20 years we have improved our management of HIV infected children requiring intensive care admission. In the absence of anti-retroviral therapy, long term outcomes from PICU admission of HIV infected children have not improved significantly, and it is debatable whether PICU admission is justified. Once anti-retroviral therapy is available to children, there may be significant improvements in outcome and possible affected children should be admitted to the PICU if resources are available.

Intracranial pressure and cerebral oxygenation changes after decompressive craniectomy in a child with traumatic brain swelling

CASE REPORT

The authors present the case of a 5-year-old child with severe traumatic brain injury in whom decompressive hemicraniectomy was performed for progressive increased intracranial pressure (ICP) unresponsive to medical treatment. Data from ICP and cerebral tissue oxygenation monitoring in the contralateral hemisphere were recorded, which demonstrated the immediate and delayed mechanical and physiological changes occurring after bony and dural decompression.

DISCUSSION

The role of the procedure and that of the monitoring approach are discussed.

The effect of epinephrine by nebulization on measures of airway obstruction in patients with acute severe croup

OBJECTIVES

To demonstrate that tests of pulmonary function applicable to sick infants and small children with acute severe viral croup would provide clear, objective evidence of responsiveness to therapy with nebulized epinephrine.

STUDY DESIGN

Oesophageal pressure changes and airflows at the mouth were measured in 17 patients with acute severe croup, before and after nebulization with epinephrine.

RESULTS

In 12 of the 17 patients there was a significant improvement in respiratory mechanics following epinephrine nebulization. Six of the 12 patients who responded to adrenaline also received 0.9% saline by nebulization, without improvement. No measures derived from combined flow and volume data showed any statistically significant change following epinephrine nebulization. Measures combining flow and pressure data, specifically inspiratory airway resistance, expiratory airway resistance, work of breathing, rate of work of breathing and volume for effort, showed changes of 26%, 33%, 16%, 16% and 46% respectively. The most statistically significant measures were pressure-rate product, pressure-time integral, oesophageal pressure alone and expiratory resistance. These changes persisted for at least 10 min after inhalation although there was some evidence of decline in pharmacologic effect at that time.

CONCLUSIONS

Nebulized epinephrine results in a short-lived improvement in some but not all patients with croup. This reduction in respiratory effort occurs secondary to a decline in inspiratory and expiratory airway resistance. Oesophageal pressures measured via a feeding tube are satisfactory for quantification of the acute response and may be a useful continuous monitoring device. Flow measurements are unhelpful, and continuous administration of nebulized epinephrine should be investigated.

Tracheostomy in human immuno-deficiency virus infected children at the Red Cross War Memorial Children's Hospital, Cape Town, South Africa

Tracheostomy in adults with HIV/AIDS has been reported to be associated with both high and early mortality of 47-100%. There is minimal data regarding the role of tracheostomy in HIV infected children. We did a retrospective analysis of HIV positive children that underwent tracheostomy at our institution over a 5-year period, 2002-2006. A total of 70 tracheostomies were done during the period and 15 (21.4%) of these children were confirmed as HIV infected. The average age at presentation for HIV infected children with upper airway obstruction resulting eventually in tracheostomy was 9.4 months and 60% were under 1 year of age. Only three (20%) were on Anti-Retroviral Therapy (ART) prior to presentation. The cause of upper airway obstruction was croup in 14 (93%) of these 15 children. Following tracheostomy all were treated with ART. To date six children have been successfully decannulated (40%) and there have been three deaths (20%) which were unrelated to tracheostomy.

CONCLUSION

Tracheostomy in HIV positive children is not associated with the high mortality that has been reported in adults provided such children are started on treatment with antiretroviral therapy.

Paediatric nonbronchoscopic bronchoalveolar lavage overview and recommendations for clinical practice

NB-BAL is an effective procedure for the diagnosis of pulmonary disease processes in ventilated infants and children. This procedure is, however, not without risks to both patients and staff. Numerous complications of NB-BAL exist, with hypoxia being themost common. As a result, care should be taken in performing NB-BAL on haemodynamically unstable patients; patients with coagulation defects; and patients with cardiac or brain abnormalities.This paper presents an overview of paediatric nonbronchoscopic bronchoalveolar lavage (NB-BAL) including: the rationale for NB-BAL; the complications associated with the procedure; indications and contraindications. It also recommends an evidence-basedclinical guideline for performing the procedure in the paediatric intensive care unit. By following the NB-BAL guidelines presented in this paper, one can ensure that an effective specimen is obtained from the lower respiratory tract, whilst minimising the risk to the patient.

A family showing recessively inherited multisystem pathology with aberrant splicing of the erythrocyte Band 7.2b ('stomatin') gene

The case of a French child, born of consanguineous parents of Tunisian origin, is described. He showed a severe multisystem disease with dyserythropoietic, sideroblastic anaemia, delayed neurological development with hypotonia and convulsions, salt-losing nephropathy, chronic watery diarrhoea, lactic acidosis with mitochondrial dysfunction, brittle hair, hypergammaglobulinaemia, fatty liver with intermittent transaminasaemia, and terminal pulmonary fibrosis. Two siblings, of both sexes, were stillborn; two more lived only a short time. One sister is alive and well. SDS gel analysis of the red cell membranes showed a deficiency within 'Band 7' at 32 kDa. Analysis of the gene encoding 'stomatin', or 'erythrocyte membrane protein 7.2b', the principal protein of 'Band 7', revealed a complex series of aberrant spliceforms centred around exon 3, for which no explanatory genomic lesion could be found. The true underlying molecular cause of this condition remains obscure, but it suggests that the stomatin gene should be studied in other cases.

Utilization of an 86 bp exon generates a novel adducin isoform (beta 4) lacking the MARCKS homology domain

A novel isoform of beta-adducin has been amplified and characterized from a human bone marrow cDNA library (GenBank #U43959). This isoform arises from the insertion of an 86 bp alternatively spliced and previously unrecognized exon (now termed exon 15) within codon 581 of the human red blood cell beta-adducin sequence. This results in an insertion of 28 novel amino acids. The remainder of the red cell beta-adducin mRNA is then translated in a different reading frame, adding an additional 35 novel amino acids prior to the stop codon. This new isoform, thus, replaces beta 1-adducin sequence after residue 580 with a total of 63 new amino acids. Sequences from genomic clones of the human beta-adducin gene show that this alternate exon is flanked by splice consensus sequences and is appropriately located in the genomic map between exons encoding up-stream and down-stream sequences, thus defining a new exon. The COOH-terminus of this new isoform, which we designate beta 4, lacks a 22 amino acid lysine-rich sequence common to both the human red cell alpha- and beta-adducin subunits and homologous to a highly conserved region in MARCKS, a filamentous actin-cross linking protein regulated by protein kinase C and calcium/calmodulin. beta 4-adducin preserves a previously identified calmodulin binding domain. PCR analysis indicates that this new beta-adducin isoform is expressed in fetal brain and liver, bone marrow, and NT-2 (neuroepithelial) cells, but is not detected in several other tissues. We anticipate that this new beta 4 isoform of beta-adducin will display unique and tissue-specific functional properties.

Guillain-Barré syndrome in South Africa associated with Campylobacter jejuni O:41 strains

Over a 20-month period, 3 adult and 6 pediatric patients were diagnosed with Guillain-Barré syndrome (GBS) at Groote Schuur and Red Cross Hospitals in Cape Town. All 9 GBS patients had Campylobacter jejuni biotype 2, serotype O:41 in their stools. C. jejuni infection was confirmed by ELISA testing of patient sera. Strains of this sero-biotype are rare: Only 12 such strains, including the GBS-associated strains, were recognized among 776 Campylobacter strains isolated and identified at Red Cross Hospital from March 1994 to October 1995. This is the first known association of C. jejuni biotype 2, serotype O:41 with GBS. Patients infected with this Campylobacter strain had a particularly severe form of the infection, requiring hospitalization and ventilation much longer than GBS patients infected with other Campylobacter species and patients with Campylobacter-negative stools. The O:41 Campylobacter isolates from the GBS patients are identical by phenotypic, serologic, and molecular criteria, and they are clonal.

Campylobacter 0:41 isolation in Guillain-Barré syndrome

Over a period of 15 months, 17 children were admitted to the Red Cross War Memorial Children's Hospital (RCWMCH) in Cape Town with Guillain-Barré syndrome. Stool specimens were collected from 14 children and campylobacter was isolated from nine. Six of the nine isolates of Campylobacter jejuni were further identified as C jejuni biotype 2, serotype 0:41. This biotype 2, serotype 0:41 has been identified in only 12 of the 7119 campylobacter isolates at the RCWMCH over a 19 year period. Eight of the nine patients with campylobacter isolates and one of five with negative stool cultures required ventilation. Patients with C jejuni biotype 2, serotype 0:41 were ventilated for a mean (SD) of 33.5 (19.4) days, whereas patients with other campylobacter isolates were ventilated for 17.3 (3.8) days. This is the first report of campylobacters of serotype 0:41 in Guillain-Barré syndrome and could reflect a geographical isolation of this strain.

Child abuse services at a children's hospital in Cape Town, South Africa

Since the establishment of a Child Abuse Management Service at the Red Cross War Memorial Children's Hospital in the early 1980s, there has been a steady increase in patient numbers. In order to assess the profile of patients, and also the allocation of staff to the service, all child abuse related patients seen at the Red Cross War Memorial Children's Hospital in Cape Town over the period of June 1989 through July 1990 were reviewed. Five hundred and three children with a median age of less than 7 years were seen. Abuse was confirmed in 389 (160 physical abuse and 229 sexual abuse). Abuse was suspected and not confirmed in 114 (41 physical and 73 sexual). Half of the patients presented to the hospital outside of normal working hours. Eighty-one percent of children less than 5 years of age were seen in the Trauma Unit by surgical residents with minimal pediatric training. One hundred and thirty four of the patients were Xhosa speaking while only one social worker and no medical staff could speak Xhosa. Pediatric residents were involved in the care of less than 2% of cases.

CONCLUSION

Management of child abuse constitutes a significant commitment and appropriate staff allocation is essential. Although it is not possible for each child in whom abuse is suspected to be seen by a specialist, they should be seen by those staff with the most expertise. Staff allocation must take into account the needs for education, training, and audit as well as service provision.

Sexually transmitted diseases in children and evidence of sexual abuse

During the period June 1989 to March 1991, laboratory evidence of sexually transmitted diseases (STDs) was found in 107 patients at the Red Cross War Memorial Children's Hospital in Cape Town. Data was available on 96 patients aged 23 months to 14 years (mean 75.9 months). Vaginal discharge was the most frequent presenting symptom (76%), particularly in those less than 5 years of age (90%). Although a history of abuse was not given on presentation in 62%, evidence of abuse was subsequently elicited in 67% of patients. Neisseria gonorrhoeae was the most common sexual pathogen (61 isolates, 8 penicillin resistant), followed by G vaginalis (17 isolates), Trichomonas vaginalis (7 infections), and T pallidum (9 TPHA positive, 5 with VDRL 1:4 or higher). Chlamydia trachomatis was demonstrated by immunofluorescence in 14 children. Multiple STDs were demonstrated in 10 patients. Although evidence of CSA was not found in all patients with STDs it was likely that the vast majority of patients had acquired these infections by CSA. Symptomatic prepubertal children with G vaginalis isolates should be investigated for CSA. Chlamydial immunofluorescence tests did not assist the diagnosis of CSA in children and should not be used, as they have no medicolegal significance.

Isolation of cDNA coding for an ubiquitous membrane protein deficient in high Na+, low K+ stomatocytic erythrocytes

Human red blood cells (RBCs) that are deficient in an integral membrane-associated protein ("stomatin") of apparent molecular mass 31 Kd show a catastrophic increase in passive membrane permeability to the univalent cations Na+ and K+ and are stomatocytic in shape. We have purified this protein from normal RBC membranes and isolated a cDNA clone coding for it. The deduced protein sequence is unrelated to that of any known ion-transport-related protein. Selective solubilization studies using detergents show that while the protein is strongly associated with the phospholipid bilayer, it also binds to the cytoskeleton. The predicted polypeptide has a single trans-membranous hydrophobic segment near the N-terminus, which would locate it in the membrane; the large C-terminal domain is hydrophilic and cytoplasmic in orientation and is presumed to be responsible for the attachment to the cytoskeleton. By inference, the protein has the function of closing a latent ion channel. The messenger RNA encoding this protein is ubiquitously distributed in different human cell types and tissues and is thus presumably a widely distributed regulator of transmembrane cation fluxes. As a membrane-bound inhibitor protein of Na+ and K+ transport, it is unique among the known components of membrane-transport proteins.

Computed tomography in agenesis of the lung in infants

This paper describes the clinical and radiological findings in three infants with agenesis of a single lung. In the two cases of right lung agenesis, severe gastro-oesophageal reflux was present. In these two cases, contrast-medium-enhanced computed tomography (CT) excluded vascular compression of major airways in one patient but demonstrated mild compression in the other. Conventional CT in the case of left lung agenesis demonstrated posterior herniation of the contralateral right lung.

Haemothorax of the newborn--an unusual cause of respiratory distress. A case report

A newborn baby with acute respiratory distress caused by tension haemothorax is described. An abnormal clotting profile indicated that the haemothorax was possibly due to a clotting deficiency. Ultrasonography was useful in establishing that the cause of the radio-opacity was fluid. The baby's problem was rapidly resolved by drainage and blood transfusion.

Comparative growth and biochemical response of very low birthweight infants fed own mother's milk, a premature infant formula, or one of two standard formulas

Very low birthweight (VLBW) infants weighing less than 1,600 g at birth were fed their own mother's milk (OMM) or randomly assigned to receive one of three formulas: a "humanized" formula (SF), a partially modified casein-predominant cow's milk formula (CF), or a premature formula (PF). All infants were fed at 120 kcal/kg/day where possible. PF infants had significantly greater weight increments (28.0 g/day) than those on OMM (19.4 g/day), SF (18.9 g/day), and CF (18.2 g/day). Those on PF also had greater increments of length, head circumference, and skin-fold thickness than those on the other two formulas and greater length increments than those on OMM. Dynamic skinfold measurements suggested that no infants accumulated excessive amounts of interstitial fluid. Infants on the two standard formulas had significantly greater base deficits, whereas those on CF also had higher urea values. Those on OMM had lower phosphate and higher alkaline phosphatase values than the other groups. Thus VLBW infants fed a premature formula had better growth and fewer biochemical problems than those on standard formulas, whereas supplementation of OMM may be necessary to ensure optimal growth and bone mineralization.

Threshold for initiation of phototherapy in infants with non-haemolytic hyperbilirubinaemia

The effect of initiating phototherapy at three different bilirubin concentrations in infants with physiological jaundice was studied in 98 clinically jaundiced term infants. Phototherapy was initiated at levels of 170, 257 and 300 mumol/l in groups A, B and C respectively. There was no difference between the groups in terms of days in hospital and bilirubin levels at entry or at exit from the study. Of group A, 97% received phototherapy v. 47% and 18% in groups B and C respectively. Peak bilirubin in those infants in group C receiving phototherapy was 318 mumol/l v. 282 mumol/l and 229 mumol/l in groups A and B. Two group C infants suffered complications of hyperbilirubinaemia. Rebound hyperbilirubinaemia was noted in infants with more severe jaundice after cessation of phototherapy. The threshold for toxicity in non-haemolytic hyperbilirubinaemia may be higher than the still widely accepted 340 mumol/l value, but pending definitive studies phototherapy will continue to be initiated at levels of greater than 257 mumol/l in term infants with hyperbilirubinaemia.

A comparison of two resuscitators in the management of birth asphyxia

Twenty newborn infants with birth asphyxia were alternately assigned to ventilation with either the Samson or the Laerdal infant resuscitator. During resuscitation significantly greater percentage changes in pH (1,1% v. 0,2%; P less than 0,05), hydrogen ion concentration (-15,6% v. -2,1%; P less than 0,05) and partial arterial carbon dioxide pressure (-24,5% v. -11,9%; P less than 0,02) were seen in the Laerdal group. There was also a tendency towards improved oxygenation and lung compliance and quicker establishment of spontaneous respiration in the Laerdal group. We therefore conclude that the Laerdal resuscitator is superior to the Samson one in the management of infants with birth asphyxia.

Precursor prothrombin status in patients receiving anticonvulsant drugs

Protein induced by vitamin K absence (PIVKA) is the circulating prothrombin precursor found in considerable concentrations when carboxylation of prothrombin is impaired. In this study PIVKA-positivity was assessed in adult epileptic patients receiving a variety of anticonvulsant drugs. Mean PIVKA (+/- SD) concentration was 4.6 +/- 2.3% in 16 epileptics vs 1.1 +/- 0.7% in 10 age-matched controls (p less than 0.001). 13 of the 16 (81%) epileptics had PIVKA values above the highest value recorded for the controls (Fisher exact test, p less than 0.001). Other indices of coagulation were normal. There was no correlation between PIVKA concentration and the particular anticonvulsant taken. This study therefore shows that most epileptics on anticonvulsant therapy have a subclinical coagulation defect. These data, together with previous findings of raised PIVKA concentrations in maternal-infant pairs exposed to gestational anticonvulsants and reports of neonatal haemorrhage in infants of epileptics, strengthen the case for antenatal vitamin K supplementation in pregnancies complicated by anticonvulsant therapy.

Eosinophilia in premature neonates. Phase 2 of a biphasic granulopoietic response

Eosinophilia within the first 6 weeks of life was studied prospectively in 10 premature neonates. Mean birthweight was 1229 +/- 314 g, and mean gestational age 31.5 +/- 1.8 weeks. Simultaneous changes in eosinophil, neutrophil, total lymphocyte, suppressor and helper T-cell counts and IgE levels were monitored. Infants were designated as responders (eosinophils greater than 1000/microliter for greater than 5 days) and non-responders. In the 6 responders eosinophils increased from 353 +/- 76 (mean +/- SEM) at birth to a peak of 2783 +/- 430/microliter at 20-25 days. Responders had significantly lower neutrophil counts at birth (P less than 0.05), and in 5 of the 6 responders neutrophils increased by more than 100% within 10-15 days; this did not occur in any of the 4 non-responders (P less than 0.025). Lymphocytes and suppressor and helper T cells increased progressively in both groups over the period of study with no differences between responders and non-responders. Birthweight and gestational age were similar in both groups, and there were no apparent causes for the lower neutrophil counts in responders at birth. Eosinophilia was not related to an IgE response. The incidence of eosinophilia in this study is similar to that reported previously, and appears to be part of a biphasic granulopoietic response.