Noninvasive hemodynamic monitoring of septic shock in children

Septic shock in children is associated with high mortality and morbidity. Its management is time-sensitive and must be aggressive and target oriented. The use of clinical assessment alone to differentiate between cold and warm shock and to select the appropriate inotropic and vasoactive medications is fraught with errors. Semi-quantitative and quantitative assessment of the preload, contractility and afterload using non-invasive tools has been suggested, in conjunction with clinical and laboratory assessment, to direct shock management and select between vasopressors, vasodilators and inotropes or a combination of these drugs. This review aims to describe non-invasive tools to assess the hemodynamic status in septic shock including echocardiography, trans-thoracic/trans-esophageal Doppler and electrical cardiometry. As septic shock is a dynamic condition that changes markedly overtime, frequent or continuous measurement of the cardiac output (CO), systemic vascular resistance (SVR) and other hemodynamic parameters using the above-mentioned tools is essential to personalize the treatment and adapt it over time. The different combinations of blood pressure, CO and SVR serve as a pathophysiological framework to manage fluid therapy and titrate inotropic and vasoactive drugs. Near infrared spectroscopy is introduced as a non-invasive method to measure end organ perfusion and assess the response to treatment.

Effect of Growth Hormone on Final Height in Children with Idiopathic Short Stature: A UAE, Eastern Region Experience

Objectives

The use of growth hormone (GH) in idiopathic short stature (ISS) has been a subject of debate for the past two decades. We sought to assess the effect of GH on final height (FH) in patients with ISS in our region, which has a high consanguinity rate, and compare it to the effect observed in GH deficient (GHD) patients.

Methods

We conducted a retrospective chart review from 1 January 2005 to 31 December 2013 for patients with ISS or GHD from the local United Arab Emirates population who received GH treatment and were followed-up regularly in our clinic. The change in height Z-score at 12 months and FH were assessed within each group and between the two groups.

Results

Twenty-one patients with ISS and 29 patients with GHD were studied. There was a significant change in height Z-score at 12 months and FH in both groups (p < 0.001). The improvement in the ISS group was comparable to the response seen in GHD patients at 12 months (0.5±0.3 standard deviation score (SDS), and 0.5±0.4 SDS, respectively; p = 0.540). The effect on FH was better in ISS group than the GHD group of all etiologies (1.3±0.6 SDS vs. 0.9±0.7 SDS, respectively; p = 0.050), there was no difference between the ISS and the subgroup of idiopathic GHD (1.3±0.5 SDS and 1.2±0.8 SDS, respectively).

Conclusions

In our local population, GH has a positive effect on the short-term growth and FH of children with ISS to the same extent that has been observed in children with idiopathic GH deficiency.

Conjugated hyperbilirubinemia presenting in first fourteen days in term neonates

AIM

To describe the etiology and characteristics of early-onset conjugated hyperbilirubinemia (ECHB) presenting within 14 d of life in term neonates.

METHODS

Retrospective review was performed of term infants up to 28-d-old who presented with conjugated hyperbilirubinemia (CHB) at a tertiary center over a 5-year period from January 2010 to December 2014. CHB is defined as conjugated bilirubin (CB) fraction greater than 15% of total bilirubin and CB greater or equal to 25 μmol/L. ECHB is defined as CHB detected within 14 d of life. “Late-onset” CHB (LCHB) is detected at 15-28 d of life and served as the comparison group.

RESULTS

Total of 117 patients were recruited: 65 had ECHB, 52 had LCHB. Neonates with ECHB were more likely to be clinically unwell (80.0% vs 42.3%, P < 0.001) and associated with non-hepatic causes (73.8% vs 44.2%, P = 0.001) compared to LCHB. Multifactorial liver injury (75.0%) and sepsis (17.3%) were the most common causes of ECHB in clinically unwell infants, majority (87.5%) had resolution of CHB with no progression to chronic liver disease. Inborn errors of metabolism were rare (5.8%) but associated with high mortality (100%) in our series. In the subgroup of clinically well infants (n = 13) with ECHB, biliary atresia (BA) was the most common diagnosis (61.5%), all presented initially with normal stools and decline in total bilirubin but with persistent CHB.

CONCLUSION

Secondary hepatic injury is the most common reason for ECHB. BA presents with ECHB in well infants without classical symptoms of pale stools and deep jaundice.

Perinatal outcome of congenital heart disease in a population with high consanguinity

OBJECTIVE

To report the perinatal pattern and outcome of fetuses with congenital heart disease (CHD) in consanguineous marriages.

METHODS

Retrospective chart review was performed for fetuses undergoing fetal echocardiography (FE) in our institution. The primary outcome was survival at 28 days after birth.

RESULTS

Between 1 January 2005 and 31 December 2010, 1950 pregnant women carrying 2151 fetuses underwent a total of 2828 FEs. CHD was diagnosed in 152 fetuses (7.1%), and perinatal outcome was available in 120, among which 78 (65%) had consanguineous parents. Thirteen fetuses died in utero, while 86 (71.7%) survived. The most prevalent lesions included left heart obstruction (25.8%), conotruncal malformations (21.7%), septal defects (18.3%), and cardiomyopathy (15.8%). Correct diagnosis was achieved in 92.2% of the cases. Extracardiac malformations occurred in 48.3% of the fetuses and were associated with increased mortality regardless of the type of CHD (P<0.001, odds ratio 6.8, 95% confidence interval 2.7-17.5).

CONCLUSION

Joint FE clinics detect most CHD with high accuracy. Consanguinity contributes to a higher prevalence of fetal cardiac and non-cardiac malformations. The presence of extracardiac anomalies is associated with an increase in perinatal mortality.

Neurally adjusted ventilator assist in very low birth weight infants: Current status

Continuous improvements in perinatal care have resulted in increased survival of premature infants. Their immature lungs are prone to injury with mechanical ventilation and this may develop into chronic lung disease (CLD) or bronchopulmonary dysplasia. Strategies to minimize the risk of lung injury have been developed and include improved antenatal management (education, regionalization, steroids, and antibiotics), exogenous surfactant administration and reduction of barotrauma by using exclusive or early noninvasive ventilatory support. The most frequently used mode of assisted ventilation is pressure support ventilation that may lead to patient-ventilator asynchrony that is associated with poor outcome. Ventilator-induced diaphragmatic dysfunction or disuse atrophy of diaphragm fibers may also occur. This has led to the development of new ventilation modes including neurally adjusted ventilatory assist (NAVA). This ventilation mode is controlled by electrodes embedded within a nasogastric catheter which detect the electrical diaphragmatic activity (Edi) and transmit it to trigger the ventilator in synchrony with the patient’s own respiratory efforts. This permits the patient to control peak inspiratory pressure, mean airway pressure and tidal volume. Back up pressure control (PC) is provided when there is no Edi signal and no pneumatic trigger. Compared with standard conventional ventilation, NAVA improves blood gas regulation with lower peak inspiratory pressure and oxygen requirements in preterm infants. NAVA is safe mode of ventilation. The majority of studies have shown no significant adverse events in neonates ventilated with NAVA nor a difference in the rate of intraventricular hemorrhage, pneumothorax, or necrotizing enterocolitis when compared to conventional ventilation. Future large size randomized controlled trials should be established to compare NAVA with volume targeted and pressure controlled ventilation in newborns with mature respiratory drive. Most previous studies and trials were not sufficiently large and did not include long-term patient oriented outcomes. Multicenter, randomized, outcome trials are needed to determine whether NAVA is effective in avoiding intubation, facilitating extubation, decreasing time of ventilation, reducing the incidence of CLD, decreasing length of stay, and improving long-term outcomes such as the duration of ventilation, length of hospital stay, rate of pneumothorax, CLD and other major complications of prematurity. In order to prevent barotrauma, next generations of NAVA equipment for neonatal use should enable automatic setting of ventilator parameters in the backup PC mode based on the values generated by NAVA. They should also include an upper limit to the inspiratory time as in conventional ventilation. The manufacturers of Edi catheters should produce smaller sizes available for extreme low birth weight infants. Newly developed ventilators should also include leak compensation and high frequency ventilation. A peripheral flow sensor is also essential to the proper delivery of all modes of conventional ventilation as well as NAVA.

Prevalence of autoantibodies in type 1 diabetes patients and its association with the clinical presentation - UAE Eastern Region experience

BACKGROUND

Positive autoantibodies and its association with the clinical course of type 1 diabetes mellitus (T1DM) have been reported worldwide, however, no such data have been reported in United Arab Emirates population.

OBJECTIVES

To study the prevalence of positive autoantibodies in T1DM pediatric patients and its association with the clinical presentation.

METHODS

Descriptive retrospective chart review of all new cases of pediatric T1DM at Tawam Hospital. Electronic patient records accessed to obtain data.

RESULTS

61 patients were identified. 88%±8.1 had at least 1 positive antibody and 82% of all patients were positive for anti-glutamic acid decarboxylase (GAD). While comparing the group of any positive antibody (n=54) with the group of all negative antibodies (n=7), a significant difference was found in the mean HbA1C (p=0.02) and nationality (p=0.03).

CONCLUSION

The vast majority of our T1DM pediatric patients are autoantibody positive, and anti-GAD antibodies were the most commonly detected antibodies.

Fibrochondrogenesis: prenatal diagnosis and outcome

We studied 20 cases with fibrochondrogenesis (FCG) diagnosed prenatally. Four cases were diagnosed at our fetal unit, and 16 cases were identified through a review of literature (in English). The prenatal diagnosis of FCG was made in 4/20 (20%). Six (30%) patients opted for termination of pregnancy (TOP). A total of 13 cases delivered at term. Four (30.8%) had a caesarean section. Four neonates (30.7%) were stillborn and seven (53.8%) neonates died within 3 months. Two infants survived beyond 3 years of age, but both had severe global developmental delay. A molecular study of the surviving children revealed two null homozygous mutations in COL11A1 [c.4084C > T (p.R1362X) and c.3708 + c.437T > G]. We concluded that the prenatal diagnosis of fibrochondrogenesis is feasible. Fibrochondrogenesis is usually a fatal disease and survivors suffer from severe physical and neurological impairment.

Risk factor assessment of young patients with acute myocardial infarction

The Middle East represents an attractive area for young individuals to seek employment, where they are exposed to numerous environmental conditions. The pursuit of a better standard of living has driven hundreds to the Middle East over the recent decades. This influx has also resulted in a predisposition to premature coronary artery disease (CAD). The aim of this study was to provide an overview of the risk factors in patients younger than 45 years, presenting with acute myocardial infarction (AMI). Out of the 148 patients analyzed, 137 were males and 11 females. 119 were from South Asia and 29 were Arabs. Their mean age was 36 ± 4.2 years. Smoking was the most prevalent risk factor in both groups at 67.6%. This was followed by hypertension, family history of CAD, hyperlipidemia and Diabetes mellitus. There was no significant difference in the clinical risk factor profile between these two groups. ST elevation myocardial infarction (STEMI) was noted in 67.6%, while 32.4% patients suffered a Non ST elevation myocardial infarction (NSTEMI). 84.5% received coronary stents, 8.8% had lone thrombus aspiration or balloon angioplasty only, while the rest were treated by conservative medical management or referred for coronary artery bypass surgery.

CONCLUSION

There is no significant difference in the CAD risk profile between young South Asian and Arab patients. Preventive strategies focused on risk factor reduction, especially smoking cessation, should be implemented to protect young adults in the most productive years of their life.

Neurally adjusted ventilatory assist (NAVA) mode as an adjunct diagnostic tool in congenital central hypoventilation syndrome

A full term female newborn was admitted to the neonatal intensive care unit (NICU) for continuous observation of apnea. Infant was noted to have apnea while asleep requiring intubation and mechanical ventilation. A video EEG was performed which demonstrated normal awake background without any seizure activity. Neurally adjusted ventilatory assist (NAVA) demonstrated the absence of electrical activity of the diaphragm (Edi) when the patient was in quiet phase of sleep. This finding on NAVA monitor raised the suspicion of central hypoventilation syndrome (CCHS) which was confirmed by genetic identification of the PHOX2B mutation.

Screening for neonatal hearing loss in the Eastern region of United Arab Emirates

The incidence of sensorineural hearing loss among infants in the neonatal intensive unit (NICU) is higher than in normal infants. This study determined the rate of hearing loss in healthy newborns and in NICU patients before hospital discharge at a single institution in the Eastern region of the United Arab Emirates; 96.5% of all eligible infants were screened. Hearing deficit was diagnosed in 25/13 854 healthy newborns (0.18%; 95% CI: 0.12%-0.27%) and 14/826 infants in the NICU (1.7%; 95% CI: 0.9%-2.8%). Although hearing impairment was significantly more common in those admitted to the NICU (RR = 9.4; 95% CI: 4.9-17.9), healthy newborns accounted for 25 of the 39 cases with hearing loss. The rate of congenital hearing deficit was comparable to international data. Universal screening is recommended since selective screening of high-risk infants missed two-thirds of newborns with hearing loss.

Renal biomarkers for assessment of kidney function in renal transplant recipients: how do they compare?

Accurate assessment of renal function is of key importance, given its prognostic value. However, gold standard measures are cumbersome, and serum creatinine itself is an insensitive predictor, especially in renal transplant recipients. Though GFR-estimating formulae have been relied upon, they do have their own limitations. Nevertheless, renal biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C, among others, are now emerging as potentially useful indicators of GFR. We aimed to evaluate the diagnostic performance of NGAL versus cystatin C and eGFR using CKD-EPI, MDRD and cystatin C in renal transplant recipients and non-transplant CKD patients. We found a significant correlation between NGAL, serum creatinine, cystatin C and eGFR. The latter parameters were also strong predictors of serum NGAL levels. However, performance of NGAL, based on receiver operating characteristic curves, was inferior to that of the reference tests. It appears that in renal transplant recipients NGAL correlates well with cystatin C and eGFR, most strongly with cystatin-based formula. Though this suggests potential use of NGAL as a screening test, its weaker diagnostic performance raises some concern about its clinical usefulness. Larger studies are needed to explore this further.

Neurally adjusted ventilatory assist mode used in congenital diaphragmatic hernia

A term baby with congenital diaphragmatic hernia (CDH) underwent surgical repair on the second day of life. Postoperatively; the oxygenation index increased to 85 despite high pressure ventilation with HFOV (high frequency oscillator ventilation) and inhaled nitric oxide therapy. Oxygenation index above 70 carries a mortality rate of 94% and merits starting extracorporeal membrane oxygenation (not available in the UAE). A trial of neurally adjusted ventilatory assist (NAVA) on the 10th postoperative day was followed by a reduction of oxygenation index to 15 and marked improvement of the clinical parameters. The EAdi (electrical activity of diaphragm) signal was relatively weak (± 5 μvolt) requiring augmentation with a high NAVA level (3 - 3.5). The patient was successfully extubated after 3 weeks.

Congenital epulis

Epulis is a rare tumour, with female preponderance that is only seen in the newborns. It arises from the mucosa of the gingiva and protrudes out of the infant's mouth. It can potentially obstruct the airways and may require an EXIT (ex-utero intrapartum treatment) procedure which involves establishing an airway before the feto-maternal circulation is interrupted. We present a female newborn with such a mass, which was diagnosed antenatally. A multidisciplinary team including the neonatologist, anaesthesiologist and ENT specialist should be present in the delivery room to establish the airways, which may require an EXIT procedure. Recommended treatment is early surgical resection. Recurrences of the tumour and damage to future dentition have not been reported, suggesting that radical excision is not warranted.

Stuve-Wiedemann syndrome: a skeletal dysplasia characterized by bowed long bones

OBJECTIVE

To describe the prenatal sonographic features of Stuve-Wiedemann syndrome (SWS).

METHODS

A retrospective review of all cases of confirmed SWS during an 8-year period was conducted. Clinical and historical data and outcome of the pregnancies were noted. Fetal biometry, skeletal survey, amniotic fluid volume and associated anomalies were recorded. A sonographic algorithm was proposed to distinguish SWS from other bent bone disorders.

RESULTS

In total, there were 10 cases, six of which were diagnosed prenatally. The main prenatal features of SWS were mild-to-moderate micromelia and bowing of the lower limb bones, affecting the tibia more than the femur. There was relative sparing of fibula and upper limb bones, with normal scapulae and clavicles. Camptodactyly was the main associated anomaly. All fetuses developed growth restriction in the late second trimester with oligohydramnios in half of the cases. These features could appear late in pregnancy. Although the thoracic dimensions were normal in the majority of fetuses, respiratory insufficiency, as a result of myotonia, was a leading cause for mortality.

CONCLUSIONS

It is possible to diagnose SWS prenatally. SWS is associated with high mortality during the first year of life, and those who survive have high morbidity.

The significance of fetal renal pelvic dilatation as a predictor of postnatal outcome

OBJECTIVES

To define the clinical outcome of fetal renal pelvic dilatation (FRPD) in cohort of infants in United Arab Emirates.

STUDY DESIGN

Data were collected from all fetuses having FRPD from January 2005 to February 2008. FRPD was graded as normal (<5 mm), mild (5-9 mm), moderate (10-15 mm), and severe (>15 mm).

RESULTS

Data from 80 fetuses with 120 kidneys were studied. Nine resolved antenatally and seven were lost to follow up. Of the remaining 89 FPRD (64 patients), 36% had normal postnatal ultrasound, 22.5% significant uropathy, and 41.5% had isolated hydronephrosis. Pelvi-ureteric junction obstruction was the commonest identified underlying abnormality. Severe FRPD predicted significant postnatal uropathy with a sensitivity of 65% and a specificity of 98.6%. Moderate FRPD increased the sensitivity to 95% but decreased the specificity to 60.9%, mild FPRD was seldom (4%) associated with significant postnatal pathology. Postnatal resolution was significantly (p = 0.01) higher in mild RPD than in the moderate or severe group.

CONCLUSION

Severe FRPD need comprehensive postnatal assessment. Although moderate FRPD had a high prevalence of uropathy, they rarely needed surgical intervention. Parents could be reassured that RPD of less than 10 mm in the third trimester is unlikely to be associated with significant uropathology.

Is isolation of outborn infants required at admission to the neonatal intensive care unit?

BACKGROUND

To measure the rate of colonization of outborn infants with methicillin-resistant Staphylococcus aureus (MRSA) to evaluate the need for Contact Precautions (including isolation) at the time of admission to the neonatal intensive care unit (NICU).

METHODS

All 239 consecutive infants referred from the neonatal units of other hospitals to a tertiary NICU in Al Ain, United Arab Emirates, between January 2000 and December 2007 were screened for MRSA colonization. Swabs from the ear, nose, rectum, axillae, and groin were obtained from each patient, and the rates of colonization were calculated retrospectively.

RESULTS

Some 72% of newborns were admitted to our NICU in the first week. Only 1 patient, admitted from Oman, grew MRSA from the ear swab (rate, 0.4%; 95% confidence interval = 0.01% approximately 2.3%).

CONCLUSION

This study from a tertiary NICU in a developing country shows that outborn infants are unlikely to harbor MRSA, and thus their routine admission in a single-bed isolation room is not justified. MRSA screening on admission has a very low yield and does not appear to be cost-effective. Contact Precautions should be reserved for those newborns transferred from general pediatric wards and those admitted from home.

Short-term outcome of very low birth weight infants in a developing country: comparison with the Vermont Oxford Network

OBJECTIVES

To determine the outcome of very low birth weight infants (VLBWI) admitted to a level III NICU in UAE and compare the results to percentiles published by the Vermont Oxford Network (VON).

METHOD

Outcome data were collected retrospectively, using standard definitions, on a cohort of VLBWI 500-1500 g admitted between January 2004 and December 2006.

RESULTS

Of the 173 infants weighing 501-1500 g at birth, 85.6% survived until discharge, which corresponds to the 50th percentile (P50) of VON. Chronic lung disease (CLD) occurred in 12.1% (<P25), death or CLD 26.6%, necrotizing enterocolitis (NEC) 5.8% (<P50), intraventricular hemorrhage (IVH) of any grade 17.5% (P25), grade III or IV IVH in 5% (P25), periventricular leucomalacia (PVL) 2.8% (P50), retinopathy of prematurity stage (ROP) 11.3% (<P10). The mortality and morbidity data for the subgroups of 501-1000 g and 1001-1500 g birth weight are also reported.

CONCLUSION

We report the outcome of VLBWI born in a developing country with high resources. The rates of CLD, IVH and ROP were < or =25th percentile of the VON and mortality, NEC and PVL were in the 50th percentile.

A newly identified splice site mutation in ZMPSTE24 causes restrictive dermopathy in the Middle East

Restrictive dermopathy (RD) is a severe neonatal inherited skin syndrome of which children die shortly after birth. Clinical features include intrauterine growth retardation, taut translucent and easily eroded skin, multiple joint ankylosis and distinct facial features. RD is usually caused by homozygous or compound heterozygous mutations in ZMPSTE24, predicted to cause loss of function of the encoded zinc metalloproteinase STE24. ZMPSTE24 is essential for the processing of the nuclear intermediate filament protein prelamin A. We report two distantly related children from the United Arab Emirates with RD. Remarkably, they lived up to 2 months, suggesting some residual function of the mutant protein. We sought to confirm the diagnosis by thorough microscopic analysis of patient skin, to identify the causative mutation and to study its functional consequences. A skin biopsy was obtained and processed for light and electron microscopy. Peripheral blood leucocytes were used for DNA and RNA isolation, and detection of prelamin A by immunofluorescence. Analysis of the skin confirmed the earlier reported densely packed collagen bundles and lack of elastin fibres. In both patients a homozygous splice site mutation c.627+1G>C in ZMPSTE24 was identified. Analysis of the ZMPSTE24 mRNA revealed an in-frame exon 5 skipping. Accumulation of prelamin A could be detected at the nuclear envelope of patient blood lymphocytes. We thus report the first splice site mutation in ZMPSTE24, which is likely to be a founder mutation in the United Arab Emirates. The accumulation of prelamin A at the nuclear periphery is consistent with defective ZMPSTE24 function. Interestingly, a regular blood sample can be used to investigate prelamin A accumulation.

Factors influencing central line infections in children with acute lymphoblastic leukemia: results of a single institutional study

BACKGROUND

We compared the rates of infection in external catheters (ECs) and totally implantable devices (TIDs) and the effect of timing of insertion in children with acute lymphoblastic leukemia (ALL).

PROCEDURE

Central line data was collected on all children with ALL referred to the National Guard Hospital, Jeddah. Data was collected retrospectively from 1996 to September 1999 and prospectively thereafter. Only ECs were inserted prior to 1999 subsequently TIDs were preferred.

RESULTS

One hundred forty eight children with ALL, mean age 5.1 years had 129 ECs and 70 TIDs inserted for a total of 41,382 catheter days. The overall rate of infective episodes (infections/1,000 catheter days) was 3.43. Of the initial 148 lines 100 developed complications of which 76 (51%) were secondary to an infective episode. Only young age and treatment protocol were risk factors for first line infections (P < 0.05). There was weak evidence that ECs had an earlier time to infection compared to TIDs (P = 0.056).

CONCLUSIONS

In this study, population central lines were associated with a high rate of infection. Treatment protocol and age were the only significant risk factors when only first lines were considered. Delaying catheter insertion for more than 3 weeks from diagnosis did not reduce the risk of infection.

Flexion contractures of the lower limbs with urogenital anomalies

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Mumps virus encephalitis can mimic herpes simplex encephalitis

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Phosphorus intake in preterm babies and variation of tubular reabsorption for phosphate per liter glomerular filtrate

Inadequate low intake of phosphorus can induce a hypophosphatemic depletion syndrome resulting in hypercalcemia, hypercalciuria, hypophosphatemia, and rickets. Tubular reabsorption for phosphate per liter glomerular filtration rate (TP/GFR) has been proposed as a reliable index of renal phosphate handling for all age groups. In the present study, carried out in 12 healthy premature babies fed unmodified pooled human milk and then a preterm formula for two periods of 10 days, we demonstrated clearly that TP/GFR as well as calciuria can reflect the poor phosphorus intake and that the kidney of preterm babies is able to rapidly adapt itself to an increase in phosphorus diet content.

Aluminium absorption in infancy

The use of aluminium-containing medications and aluminium contamination of infant formulae is common. We aimed to determine whether aluminium absorption occurs after antacid ingestion. Plasma and urinary levels of aluminium were measured before and after antacid therapy in seven infants whose mean gestational age was 36 +/- 2 weeks and postnatal age 11 +/- 5 days. Antacid therapy (400-800 mumol aluminium) was given with feeds for 2 days. Plasma aluminium levels increased and reached toxic levels (0.64 +/- 0.33 mumol/L vs 3.48 +/- 2.86 mumol/L, P = 0.029). Urinary aluminium: creatinine ratio also increased. These results demonstrate that infants absorb aluminium from antacids and raise the concern of aluminium toxicity.