Displaying all 14 publications

Abstract:
Sort:
  1. Williams J, Abdul Wahab AH, Leman WI
    Cureus, 2024 Apr;16(4):e57428.
    PMID: 38699091 DOI: 10.7759/cureus.57428
    Thyroid abscess, or acute suppurative thyroiditis (AST), is an exceedingly rare condition, particularly in the pediatric population. It often results from congenital anomalies or is secondary to infections. Despite its rarity, prompt diagnosis and management are crucial to prevent serious complications. We report a case of a five-year-old girl with no significant medical history who presented with a two-week history of anterior neck swelling, odynophagia, fever, and leukocytosis. Notably, the patient did not exhibit symptoms of thyroid dysfunction. Initial treatment with antibiotics for a suspected bacterial infection at a private clinic did not lead to improvement. Ultrasound and computed tomography scans revealed a multiloculated abscess within the left thyroid lobe. The patient underwent successful incision and drainage, supported by antibiotic therapy, resulting in a full recovery without complications. Imaging studies played a critical role in diagnosing and guiding the management of this condition. Thyroid abscess, though rare, should be part of the differential diagnosis for pediatric patients presenting with acute neck swelling, fever, and pain. Early diagnosis and appropriate management, typically involving surgical drainage and antibiotics, are essential for a favorable outcome.
  2. Mohmad Zaki N, Abdul Wahab AH
    Cureus, 2024 Jul;16(7):e65485.
    PMID: 39188482 DOI: 10.7759/cureus.65485
    Parotid neoplasm in children is very rare, and most of these tumors are benign. Parotid enlargement in children is usually caused by infection or inflammation. We report a case of a 12-year-old boy who presented with the initial manifestation of bilateral parotid enlargement. He complained of two weeks of parotid swelling, during which the tumor gradually increased in size as he battled a monthlong on-and-off fever. An intravenous antibiotic was administered, as the first diagnosis was infection. Imaging studies of the swelling displayed features of infection, which was not resolved by the antibiotic. Fine-needle aspiration cytology was initially planned to establish a diagnosis. However, due to other findings in the clinical examination, such as bilateral scrotal swelling with abnormal blood work, the child was referred to other specialists for further assessment. Eventually, he was diagnosed with B-cell acute lymphoblastic leukemia by a hematology team.
  3. Ho AZJ, Abdul Wahab AH, Rozhan A
    Cureus, 2024 Jun;16(6):e61712.
    PMID: 38975550 DOI: 10.7759/cureus.61712
    Papillary thyroid carcinoma (PTC) is a common malignancy originating from the thyroid gland. In rare cases, it can invade the trachea, resulting in airway obstruction. Subsequent surgical planning may be complicated as the technique selected depends on a case-by-case basis. Here, we report a case of PTC with tracheal involvement and a literature review on the latest surgical options. A 56-year-old gentleman presented with an anterior neck swelling of 3 x 3 cm for 3 months. Flexible endoscopy showed irregular mass in the subglottic region. Subsequent aspiration for cytology confirmed a diagnosis of PTC. Neck contrast enhanced computed tomography showed an ill-defined lesion in the right thyroid (3.1 x 3.8 x 2.9 cm) with a subtle irregularity of the adjacent tracheal wall suggestive of infiltration. The findings indicated a clinical staging of cT4aN0M0 (Stage III) with Shin's staging of Stage IV. The patient underwent a total thyroidectomy and a single-stage partial cricoid-tracheal resection with anastomosis. There were no immediate post-operative complications reported. Unfortunately, the patient suffered from pulmonary embolism, which eventually resulted in his demise. A subsequent histopathology report confirmed the diagnosis of PTC. Surgical planning for such cases may be complicated. The risk of recurrent laryngeal nerve injury is increased as the site of resection is close to the nerve. Multiple intraoperative nerve monitoring systems may be required. Meticulous planning of intraoperative airway management is needed as a large intraluminal tumor may interfere with intubation. Generally, extensive tracheal invasion would require radical surgical approaches such as circumferential resection and total laryngectomy. Less extensive cases can be treated with shave excision or window resection. PTC with tracheal invasion is an uncommon condition, and surgical excision is indicated for cases with high Shin's staging.
  4. Yung Chwen WL, Abdul Wahab AH, Ahmad Affandi K
    Cureus, 2024 Oct;16(10):e72381.
    PMID: 39583538 DOI: 10.7759/cureus.72381
    Papillary thyroid carcinoma often emerges within the middle-aged group as a painless, irregular thyroid mass, and it can be accompanied by other symptoms such as hoarseness and dysphagia. Cervical node metastasis typically involves the ipsilateral jugular chain and remains confined to cervical node levels III and IV in most of the patients. Here, we present a case highlighting the uncommon presentation of papillary thyroid carcinoma. A 63-year-old Malay man with no known medical issues initially exhibited a painless swelling on the right neck level V region. The swelling progressively grew in size and later extended toward the anterior and contralateral sides of the neck for a duration of a year. He reported a weight loss of 10 kg past a year and experienced consistent fatigue. Physical examination showed multiple firm swellings with regular borders over levels I to V bilaterally. The swellings did not move upon swallowing. Due to the absence of initial thyroid swelling and the presence of multiple cervical lymphadenopathies in his medical history, lymphoma was suspected. A referral to ENT was made for an excision biopsy, but the procedure was abandoned to prevent potential injury to important underlying structures such as blood vessels and nerves. An ultrasound-guided biopsy was subsequently performed over multiple neck regions. It resulted in papillary thyroid carcinoma instead of lymphoma. Despite a suggestive history of lymphoma, papillary thyroid carcinoma should be considered a potential differential for a multilobulated neck mass. Excision biopsy has the potential to upstage the tumor and worsen the patient's prognosis. Fine-needle aspiration for cytology should be prioritized when investigating any neck swelling.
  5. Chua KB, Mustafa B, Abdul Wahab AH, Chem YK, Khairul AH, Kumarasamy V, et al.
    Malays J Pathol, 2011 Jun;33(1):13-20.
    PMID: 21874746
    A prospective study was carried out to evaluate the sensitivity of dengue NS1 antigen-capture ELISA in comparison with dengue virus isolation, conventional RT-PCR and real-time RT-PCR for laboratory confirmation of acute dengue based on single-acute serum samples. Four primary healthcare centres were involved to recruit patients with clinical diagnosis of dengue illness. Patient's demographic, epidemiological and clinical information were collected on a standardized data entry form and 5 ml of venous blood was collected upon consent. In the laboratory, six types of laboratory tests were performed on each of the collected acute serum sample. Of the 558 acute serum samples collected from 558 patients with clinical diagnosis of dengue from mid-August 2006 to March 2009, 174 serum samples were tested positive by the dengue NS1 antigen-capture ELISA, 77 by virus isolation, 92 by RT-PCR and 112 by real-time RT-PCR. A total of 190 serum samples were tested positive by either one or a combination of the four methods whereas, only 59 serum samples were tested positive by all four methods. Thus, based on single-acute serum samples, 190 of the 558 patients (34.1%) were laboratory-confirmed acute dengue. The overall test sensitivity was 91.6%, 40.5%, 48.4% and 58.9% for dengue NS1 antigen-capture ELISA, virus isolation, conventional RT-PCR and real-time RT-PCR respectively. Statistically, dengue NS1 antigen-capture ELISA was the most sensitive and virus isolation was the least sensitive test for the laboratory confirmation of acute dengue based on single-acute serum specimens. Real-time RT-PCR was significantly more sensitive than the conventional RT-PCR.
  6. Wahab AH, Kadir MR, Harun MN, Kamarul T, Syahrom A
    Med Biol Eng Comput, 2017 Mar;55(3):439-447.
    PMID: 27255451 DOI: 10.1007/s11517-016-1525-6
    The present study was conducted to compare the stability of four commercially available implants by investigating the focal stress distributions and relative micromotion using finite element analysis. Variations in the numbers of pegs between the implant designs were tested. A load of 750 N was applied at three different glenoid positions (SA: superior-anterior; SP: superior-posterior; C: central) to mimic off-center and central loadings during activities of daily living. Focal stress distributions and relative micromotion were measured using Marc Mentat software. The results demonstrated that by increasing the number of pegs from two to five, the total focal stress volumes exceeding 5 MPa, reflecting the stress critical volume (SCV) as the threshold for occurrence of cement microfractures, decreased from 8.41 to 5.21 % in the SA position and from 9.59 to 6.69 % in the SP position. However, in the C position, this change in peg number increased the SCV from 1.37 to 5.86 %. Meanwhile, micromotion appeared to remain within 19-25 µm irrespective of the number of pegs used. In conclusion, four-peg glenoid implants provide the best configuration because they had lower SCV values compared with lesser-peg implants, preserved more bone stock, and reduced PMMA cement usage compared with five-peg implants.
  7. Abd Aziz AU, Abdul Wahab AH, Abdul Rahim RA, Abdul Kadir MR, Ramlee MH
    Injury, 2020 Nov;51(11):2474-2478.
    PMID: 32798038 DOI: 10.1016/j.injury.2020.08.001
    In an open fracture, the external fixator is one of the definitive treatment options as it could provide the initial stabilisation of the fractured bone. Limited literature discussing on the biomechanical stability between unilateral, hybrid and Ilizarov configurations, principally in treating a femoral fracture. Thus, this study aims to analyse the biomechanical stability of different external fixators via the finite element method (FEM). The present study portrays that different configurations of fixators possess different biomechanical stability, hence leading to different healing rates and complication risks. For the methodology, three-dimensional models of three different external fixators were reconstructed where axial loads were applied on the proximal end of the femur, simulating the stance phase. From the results, the unilateral configuration provides better stability compared to the hybrid and Ilizarov, where it displaced the least with an average percentage difference of 50% for the fixator's frame and 23% for the bone. The unilateral configuration also produced the least interfragmentary movement (0.48 mm) as compared to hybrid (0.62 mm) and Ilizarov (0.61 mm) configurations. Besides, the strain and stress of the unilateral configuration were superior in terms of stability compared to the other two configurations. As a conclusion, the unilateral configuration had the best biomechanical stability as it was able to assist the bone healing process as well as minimising the risk of pin tract infection while treating a femoral fracture.
  8. Abdul Wahab AH, Wui NB, Abdul Kadir MR, Ramlee MH
    Comput Biol Med, 2020 12;127:104062.
    PMID: 33096298 DOI: 10.1016/j.compbiomed.2020.104062
    External fixators have been widely used in treating open fractures and have produced excellent outcomes, as they could successfully heal bones. The stability of external fixators lies greatly in their construction. Factors that associated with the stability of the external fixators includes stress, displacement, and relative micromotion. Three-dimensional (3D) models of bone and external fixators were constructed by using 3D modelling software, namely Materialise and SolidWorks, respectively. Three different configurations of external fixators namely Model 1, Model 2, and Model 3 were analysed. Three load cases were simulated to assess the abovementioned factors at the bone, specifically at the fracture site and at the external fixator. Findings showed that the double-cross configuration (Model 3) was the most promising in axial, bending, and torsion load cases as compared to the other two configurations. The no-cross configuration (Model 1) had the highest risk of complication due to high stress, relative micromotion, and displacement in the bending and torsion load cases. On the other hand, the single-cross configuration (Model 2) had the highest risk of complication when applied with axial load. In conclusion, the double-cross locking construct (Model 3) showed the biggest potential to be a new option for medical surgeons in treating patients associated with bone fracture. This new double-cross locking construct showed superior biomechanical stability as compared to single-cross and no-cross configurations in the axial, bending, and torsion load cases.
  9. Zainal Abidin NA, Abdul Wahab AH, Abdul Rahim RA, Abdul Kadir MR, Ramlee MH
    Med Biol Eng Comput, 2021 Sep;59(9):1945-1960.
    PMID: 34392448 DOI: 10.1007/s11517-021-02419-6
    Complication rates of anterior cruciate ligament reconstruction (ACL-R) were reported to be around 15% although it is a common arthroscopic procedure with good outcomes. Breakage and migration of fixators are still possible even months after surgery. A fixator with optimum stability can minimise those two complications. Factors that affect the stability of a fixator are its configuration, material, and design. Thus, this paper aims to analyse the biomechanical effects of different types of fixators (cross-pin, interference screw, and cortical button) towards the stability of the knee joint after ACL-R. In this study, finite element modelling and analyses of a knee joint attached with double semitendinosus graft and fixators were carried out. Mimics and 3-Matic softwares were used in the development of the knee joint models. Meanwhile, the graft and fixators were designed by using SolidWorks software. Once the meshes of all models were finished in 3-Matic, simulation of the configurations was done using MSC Marc Mentat software. A 100-N anterior tibial load was applied onto the tibia to simulate the anterior drawer test. Based on the findings, cross-pin was found to have optimum stability in terms of stress and strain at the femoral fixation site for better treatment of ACL-R.
  10. Abdul Wahab AH, Mohamad Azmi NA, Abdul Kadir MR, Md Saad AP
    Int J Artif Organs, 2022 Feb;45(2):200-206.
    PMID: 33645338 DOI: 10.1177/0391398821999391
    Glenoid conformity is one of the important aspects that could contribute to implant stability. However, the optimal conformity is still being debated among the researchers. Therefore, this study aims to analyze the stress distribution of the implant and cement in three types of conformity (conform, non-conform, and hybrid) in three load conditions (central, anterior, and posterior). Glenoid implant and cement were reconstructed using Solidwork software and a 3D model of scapula bone was done using MIMICS software. Constant load, 750 N, was applied at the central, anterior, and posterior region of the glenoid implant which represents average load for daily living activities for elder people, including, walking with a stick and standing up from a chair. The results showed that, during center load, an implant with dual conformity (hybrid) showed the best (Max Stress-3.93 MPa) and well-distributed stress as compared to other conformity (Non-conform-7.21 MPa, Conform-9.38 MPa). While, during eccentric load (anterior and posterior), high stress was located at the anterior and posterior region with respect to the load applied. Cement stress for non-conform and hybrid implant recorded less than 5 MPa, which indicates it had a very low risk to have cement microcracks, whilst, conform implant was exposed to microcrack of the cement. In conclusion, hybrid conformity showed a promising result that could compromise between conform and non-conform implant. However, further enhancement is required for hybrid implants when dealing with eccentric load (anterior and posterior).
  11. Kumarasamy V, Chua SK, Hassan Z, Wahab AH, Chem YK, Mohamad M, et al.
    Singapore Med J, 2007 Jul;48(7):669-73.
    PMID: 17609831
    INTRODUCTION: The aim of this report is to establish an accurate diagnosis of acute dengue virus infection early, in order to provide timely information for the management of patients and early public health control of dengue outbreak.
    METHODS: 224 serum samples from patients with a clinical diagnosis of acute dengue infection, which were subsequently confirmed by laboratory tests, were used to evaluate the performance of a commercially-available dengue NS1 antigen-capture ELISA kit.
    RESULTS: The dengue NS1 antigen-capture ELISA gave an overall sensitivity rate of 93.3 percent (209/224). The sensitivity rate was significantly higher in acute primary dengue (97.4 percent) than in acute secondary dengue (68.8 percent). In comparison, the virus isolation gave an overall positive isolation rate of 64.7 percent, with a positive rate of 70.8 percent and 28.1 percent, for acute primary dengue and acute secondary dengue, respectively. Molecular detection of dengue RNA by RT-PCR gave an overall positive detection rate of 63.4 percent, with a positive rate of 62.5 percent and 68.8 percent, for acute primary dengue and acute secondary dengue, respectively. Of the 224 acute serum samples from patients with laboratory-confirmed acute dengue infection, dengue IgM was detected in 88 specimens, comprising 68 acute primary dengue specimens and 20 acute secondary dengue specimens. NS1 antigen-capture ELISA kit gave an overall sensitivity rate of 88.6 percent in the presence of anti-dengue IgM and 96.3 percent in the absence of anti-dengue IgM.
    CONCLUSION: Of the 224 acute serum samples, the sample ages of 166 acute serum samples are known. The positive detection rate of dengue NS1 antigen-capture ELISA, on the whole, was higher than the other three established diagnostic test methods for laboratory diagnosis of acute dengue infection.
  12. Kumarasamy V, Wahab AH, Chua SK, Hassan Z, Chem YK, Mohamad M, et al.
    J Virol Methods, 2007 Mar;140(1-2):75-9.
    PMID: 17140671
    A commercial dengue NS1 antigen-capture ELISA was evaluated to demonstrate its potential application for early laboratory diagnosis of acute dengue virus infection. Dengue virus NS1 antigen was detected in 199 of 213 acute serum samples from patients with laboratory confirmation of acute dengue virus infection but none of the 354 healthy blood donors' serum specimens. The dengue NS1 antigen-capture ELISA gave an overall sensitivity of 93.4% (199/213) and a specificity of 100% (354/354). The sensitivity was significantly higher in acute primary dengue (97.3%) than in acute secondary dengue (70.0%). The positive predictive value of the dengue NS1 antigen-capture ELISA was 100% and negative predictive value was 97.3%. Comparatively, virus isolation gave an overall positive isolation rate of 68.1% with a positive isolation rate of 73.9 and 31.0% for acute primary dengue and acute secondary dengue, respectively. Molecular detection of dengue RNA by RT-PCR gave an overall positive detection rate of 66.7% with a detection rate of 65.2 and 75.9% for acute primary dengue and acute secondary dengue, respectively. The results indicate that the commercial dengue NS1 antigen-capture ELISA may be superior to virus isolation and RT-PCR for the laboratory diagnosis of acute dengue infection based on a single serum sample.
  13. Zainah S, Wahab AH, Mariam M, Fauziah MK, Khairul AH, Roslina I, et al.
    J Virol Methods, 2009 Feb;155(2):157-60.
    PMID: 19022293 DOI: 10.1016/j.jviromet.2008.10.016
    The performance of a commercial immunochromatography test for rapid detection of dengue NS1 antigen present in serum or plasma of patients was evaluated against a commercial dengue NS1 antigen-capture ELISA. The rapid immunochromatography test gave an overall sensitivity of 90.4% with a specificity of 99.5%. The sensitivity was highest for serum samples from which virus was isolated (96.3%) and lowest for those from which virus was not isolated and RT-PCR was negative (76.4%). The sensitivity was significantly higher for serum samples from patients with acute primary dengue (92.3%) than those from patients with acute secondary dengue (79.1%). The positive predictive value and negative predictive value of this commercial immunochromatography test were 99.6% and 87.9% respectively.
  14. Chew CH, Woon YL, Amin F, Adnan TH, Abdul Wahab AH, Ahmad ZE, et al.
    BMC Public Health, 2016 08 18;16(1):824.
    PMID: 27538986 DOI: 10.1186/s12889-016-3496-9
    BACKGROUND: Each year an estimated 390 million dengue infections occur worldwide. In Malaysia, dengue is a growing public health concern but estimate of its disease burden remains uncertain. We compared the urban-rural difference of dengue seroprevalence and determined age-specific dengue seroprevalence in Malaysia.

    METHODS: We undertook analysis on 11,821 subjects from six seroprevalence surveys conducted in Malaysia between 2001 and 2013, which composed of five urban and two rural series.

    RESULTS: Prevalence of dengue increased with age in both urban and rural locations in Malaysia, which exceeded 90 % among those aged 70 years or beyond. The age-specific rates of the 5 urban surveys overlapped without clear separation among them, while prevalence was lower in younger subjects in rural series than in urban series, the trend reversed in older subjects. There were no differences in the seroprevalence by gender, ethnicity or region. Poisson regression model confirmed the prevalence have not changed in urban areas since 2001 but in rural areas, there was a significant positive time trend such that by year 2008, rural prevalence was as high as in urban areas.

    CONCLUSION: Dengue seroprevalence has stabilized but persisted at a high level in urban areas since 2001, and is fast stabilizing in rural areas at the same high urban levels by 2008. The cumulative seroprevalence of dengue exceeds 90 % by the age of 70 years, which translates into 16.5 million people or 55 % of the total population in Malaysia, being infected by dengue by 2013.

Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links