GCF Chan

For some common paediatric health problems, one does not have to use sophisticated technology to arrive at the diagnosis. However, proper understanding of the pros and cons related to each diagnostic test is important. Akbayram HT, et al reported their experience of using common erythrocytes indices to distinguish those iron deficient patients who developed anaemia. In his finding, only 15.5% of patients with iron deficiency have concomitant anaemia. They all have low MCV, MCH, MCHC and high red cell distribution width (RDW). To most of us, it sounds like stating the obvious but in reverse, how often do we see our patients with low iron status but without anaemia? In classical teaching, total iron binding capacity is the best index to reflect the low iron state. Serum ferritin tends to underestimate the low iron storage for it is an acute phase reactant. Therefore, this retrospective review may probably miss some patients with low iron status because ferritin instead of TIBC was used to measure the body's iron. Another precaution in applying the knowledge of this article is the prevalence of thalassaemia carriers in a particular population. The red cells indices are very similar between iron deficiency anaemia and thalassemia carrier except for the erythrocytes number tends to be higher (usually >4.5 x10⁹/L) for thalassaemia carrier and lower (usually <4x10⁹/L) for iron deficiency, which is the basis of the famous Menzer's index which was designed to distinguish the two conditions.

Ultrasound is a common bed side tests for neonates for it is free from radiation hazard and less affected by the mobility of the tested subjects. But like other diagnostic tests, it may over-diagnose some benign conditions and lead to unnecessary concerns. Renal medullary hyper-echogenicity has been reported in newborns with severe perinatal kidney damage, renal malformation, nephrocalcinosis, and in newborns with transient acute kidney injury. Tas M, et al reported 20 newborn patients with transient RMH and despite having a transient elevated serum creatinine (2/3) and urinary protein (1/3), all patients became completely normal biochemically and sonographically within a few days. Therefore, majority of renal medullary hyper-echogenicity in newborns can be a transient condition and will subside even without any specific treatment. Reassurance can be given to parents with newborns having this finding to avoid unnecessary anxiety.

Dynamic balance is the ability of a person to actively control his/her body position and posture when moving without falling. In patients with either hemiplegia or diplegia, this can be a challenge. How to objectively assess their dynamic balance remains elusive. Tanrioger Soyuer F, et al described an easy, cheap and robust method known as Four-Square Step Test (FSST) to assess the dynamic balance ability of adolescent patients with cerebral palsy. The is a dynamic standing balance test that was designed to assess a patient's ability to rapidly cross over obstacles and change of direction. The FSST requires minimal time, space and equipment. The study shows that the FSST is a valid and reliable test to evaluate dynamic standing balance in adolescents with cerebral palsy.

Velopharyngeal dysfunction (VPD) is a clinical condition in which patients having inadequate separation of the oral and nasal cavities during speech or swallowing. It is due to either structural and/or functional abnormalities of the soft palate and the pharyngeal muscles. It may impact on the patients' swallowing and speech function. Two groups of patients, including those with cleft palate and those with a genetic defect of 22q11.2 microdeletion (22qDS) having intact but dysfunction palate, have VPD. Tang PMY, et al reported the short-term outcome of 12 patients with congenital cleft palate after surgical repair and 8 patients with 22qDS (2 did not having operation) and concluded for those who underwent surgical repair, no major complications noted, and all achieved functional improvement. One of the key messages is that VPD with intact palate associated with 22qDS can be easily missed. The awareness of this association and diagnosis using fluorescence in situ hybridisation (FISH) method can help to establish the diagnosis. Timely diagnosis of 22qDS is important for early surgical intervention with rehabilitation can markedly improve the speech and swallowing function of these patients.

All these studies reveal a similar theme that common or simple diagnostic tests can be applied clinically to facilitate diagnosis and guide our management. However, thorough understanding of the principle and limitations of these tests are essential. In an era with rapid advancement in medical technology, over-investigation with sophisticated or expensive tests is the trends. At time, we must return to the basic in solving our clinical problems with minimal and simple investigations, especially when we are practicing clinical medicine under a non-hospital-based setting.