MyMedR

Displaying publications 21 - 30 of 30 in total

Abstract:

Sort:

Cellulitis due to Shewanella algae: Crucial diagnostic clues from basic microbiological tests

Ding CH, Wahab AA, Muttaqillah NAS, Kamarudin N, Saarah WR

Trop Biomed, 2019 Dec 01;36(4):883-887.
PMID: 33597461

Shewanella spp. are infrequently implicated in human infections but they are emerging pathogens with particular significance in regions with warm climates, such as Southeast Asia. This is a case of a middle-aged diabetic and hypertensive man who presented with worsening congestive heart failure symptoms associated with fever and a painful right leg. His right leg had numerous scabs and was tender, warm and erythematous. He was provisionally diagnosed with decompensated heart failure precipitated by cellulitis and uncontrolled hypertension. His blood grew non-fermentative, oxidase-positive and motile gram-negative bacilli which produced hydrogen sulfide on triple sugar iron agar. When cultured on blood agar, mucoid and weakly β-haemolytic colonies were observed after 48 hours. API 20 NE named the isolate as Shewanella putrefaciens but 16S rRNA sequence analysis identified the organism as Shewanella algae. The patient was treated with a 10-day course of ceftazidime, which resulted in the resolution of the cellulitis.
The reliability of a rapid molecular detection method in determining the prevalence of rifampicin-resistant Mycobacterium tuberculosis in an urban district health facility in Malaysia

Ding CH, Ismail Z, Sulong A, Wahab AA, Gan B, Mustakim S, et al.

Malays J Pathol, 2020 Dec;42(3):401-407.
PMID: 33361721

INTRODUCTION: Rifampicin is a key first-line antimycobacterial agent employed for the treatment of pulmonary tuberculosis (PTB). This study sought to obtain prevalence data on rifampicin-resistant Mycobacterium tuberculosis among smear-positive PTB patients in the Klang District of Malaysia.
MATERIALS AND METHODS: A total of 103 patients from the Chest Clinic of Hospital Tengku Ampuan Rahimah with sputum smears positive for acid-fast bacilli were included in this cross-sectional study. All sputa were tested using Xpert MTB/RIF to confirm the presence of M. tuberculosis complex and detect rifampicin resistance. Sputa were also sent to a respiratory medicine institute for mycobacterial culture. Positive cultures were then submitted to a reference laboratory, where isolates identified as M. tuberculosis complex underwent drug susceptibility testing (DST).
RESULTS: A total of 58 (56.3%) patients were newly diagnosed and 45 (43.7%) patients were previously treated. Xpert MTB/RIF was able to detect rifampicin resistance with a sensitivity and specificity of 87.5% and 98.9%, respectively. Assuming that a single resistant result from Xpert MTB/RIF or any DST method was sufficient to denote resistance, a total of 8/103 patients had rifampicinresistant M. tuberculosis. All eight patients were previously treated for PTB (p<0.05). The overall prevalence of rifampicin resistance among smear-positive PTB patients was 7.8%, although it was 17.8% among the previously treated ones.
CONCLUSION: The local prevalence of rifampicin-resistant M. tuberculosis was particularly high among previously treated patients. Xpert MTB/RIF can be employed in urban district health facilities not only to diagnose PTB in smear-positive patients, but also to detect rifampicin resistance with good sensitivity and specificity.
Fulltext The crucial role of molecular testing to facilitate the diagnosis of pneumocystis pneumonia during pregnancy

Ding CH, Yusoff H, Muttaqillah NAS, Tang YL, Tan TL, Periyasamy P, et al.

Malays J Pathol, 2018 Apr;40(1):69-72.
PMID: 29704387 MyJurnal

Pneumocystis pneumonia is an important human immunodeficiency virus (HIV)-associated opportunistic infection, and especially so in pregnant HIV-positive patients. We report a case of a 40-year-old woman in her first trimester of pregnancy who initially presented with acute gastroenteritis symptoms but due to a history of high-risk behaviour and the observation of oral thrush, she was worked up for HIV infection. Her retroviral status was positive and her CD4+ T cell count was only 8 cells/µL. She was also worked up for pneumocystis pneumonia due to the presence of mild resting tachypnoea and a notable drop in oxygen saturation (from 100% to 88%) following brief ambulation. Her chest radiograph revealed bilaterally symmetrical lower zone reticular opacities and Giemsa staining of her bronchoalveolar lavage (BAL) was negative for Pneumocystis jirovecii cysts. However, real-time P. jirovecii polymerase chain reaction (PCR) testing on the same BAL specimen revealed the presence of the organism. A course of oral co-trimoxazole plus prednisolone was commenced and her clinical condition improved.
Fulltext Exophiala dermatitidis, 'the real black fungus' fungemia in a patient with COVID-19

Tzar MN, Meor Jamaludin WHB, Abdul Wahab A, Ding CH

IDCases, 2022;27:e01428.
PMID: 35127454 DOI: 10.1016/j.idcr.2022.e01428

The second wave of the COVID-19 pandemic in India had brought with it a surge of 'black fungus' co-infection, which is a misnomer for mucormycosis. The present case illustrates the 'real black fungus' infection in a 50-year old male patient with COVID-19 pneumonia, who otherwise had no significant previous medical history. He was admitted on day 8 of COVID-19 illness and was intubated due to persistently low oxygen saturation. Blood cultures were positive for flask-shaped dematiaceous budding yeasts with pseudohyphae formation, which grew as brown-black fuzzy colonies on Sabouraud dextrose agar. The isolate was identified as Exophiala dermatitidis based on phenotypic characterization. Despite antifungal therapy with amphotericin B and itraconazole, the patient deteriorated rapidly and succumbed to acute respiratory distress syndrome and multiorgan failure. A review of reported cases of Exophiala dermatitidis fungemia over the last 5-years is discussed.
Fulltext Isolation of an obscure fungus, Parengyodontium album, from the blood of a severely neutropenic patient: The first reported case from Malaysia

Mohamed N, Ding CH, Wahab AA, Tzar MN, Hassan M

J Infect Dev Ctries, 2022 Oct 31;16(10):1668-1670.
PMID: 36332225 DOI: 10.3855/jidc.17016

Parengyodontium album is a very rarely encountered opportunistic fungal pathogen. A severely neutropenic 11-year-old boy with acute T-cell lymphoblastic leukemia/lymphoma was febrile and lethargic during his admission for elective chemotherapy. No cutaneous lesion or obvious source of infection was noted, and clinical examination was otherwise unremarkable. A blood specimen was sent for culture and fungal elements were visualized. Amphotericin B was administered empirically while awaiting fungal identification. Morphologically, a hyaline mould with thin septate hyphae plus smooth-walled conidiophores and conidiogenous cells arranged in whorls of up to four was cultured. Internal transcribed spacer region sequencing identified the fungus conclusively as P. album. Repeat blood culture was also positive for the same fungus. Following a two-week course of amphotericin B, fungemia clearance was attained.
Adult-onset nasopharyngeal diphtheria: an uncommon but rapidly progressive and potentially fatal infection

Ding CH, Wahab AA, Marina Z, Leong CL, Umur N, Wong PF

Trop Biomed, 2021 Jun 01;38(2):119-121.
PMID: 34172699 DOI: 10.47665/tb.38.2.045

Nasopharyngeal diphtheria is an acute infectious upper respiratory tract disease caused by toxigenic strains of Corynebacterium diphtheriae. We report a case of a young adult who presented to us with a short history of fever, sore throat, hoarseness of voice and neck swelling. He claimed to have received all his childhood vaccinations and had no known medical illnesses. During laryngoscopy, a white slough (or membrane) was seen at the base of his tongue. The epiglottis was also bulky and the arytenoids were swollen bilaterally. The membrane was sent to the microbiology laboratory for culture. A diagnosis of nasopharyngeal diphtheria was made clinically and the patient was treated with an antitoxin together with erythromycin, while awaiting the culture result. Nevertheless, the patient's condition deteriorated swiftly and although the laboratory eventually confirmed an infection by toxin-producing C. diphtheriae, the patient had already succumbed to the infection.
Non-bacteremia liver abscess caused by Burkholderia pseudomallei from a tertiary teaching hospital in Malaysia: a case report and literature review

Wahab AA, Nurazizah SMA, Ding CH, Muttaqillah NAS, Nordashima AS, Kori N, et al.

Trop Biomed, 2023 Sep 01;40(3):290-294.
PMID: 37897160 DOI: 10.47665/tb.40.3.003

Melioidosis is endemic in Southeast Asia, including Malaysia. Liver abscess is not uncommon in melioidosis, but it is usually associated with bacteremia. We presented a case of a 55-year-old gentleman with underlying end-stage renal failure who presented with non-specific abdominal pain for three months. Initial blood investigations showed leukocytosis and increased C-reactive protein. Computed tomography (CT) of the abdomen revealed multiple hypodense lesions in the liver and spleen. The culture of the liver specimen obtained through the ultrasound-guided isolated Burkholderia pseudomallei. He was given an adjusted dose of intravenous ceftazidime due to underlying renal failure. Melioidosis serology also returned positive for IgM with titer >1:1280. His blood cultures were reported negative three times. Despite on antibiotics for five weeks, there was no significant improvement of the liver abscesses was observed. He was unfortunately infected with the SARS-CoV-2 virus during his admission and passed away due to severe COVID-19 pneumonia.
Antifungal susceptibility profile and biofilm-producing capability of Candida tropicalis isolates in a tertiary medical centre

Navarathinam SD, Neoh HM, Tan TL, Wahab AA, Mohd Nizam Tzar MN, Ding CH

Malays J Pathol, 2023 Dec;45(3):417-424.
PMID: 38155383

BACKGROUND: Candida tropicalis is a globally distributed yeast that has been popping up in the medical literature lately, albeit for unenviable reasons. C. tropicalis is associated with substantial morbidity, mortality as well as drug resistance. The aims of this study were to ascertain the antifungal susceptibility profile and the biofilm-producing capability of this notorious yeast in our centre.
METHODS: C. tropicalis isolates from sterile specimens were collected over a 12-month period. Conclusive identification was achieved biochemically with the ID 32 C kit. Susceptibility to nine antifungal agents was carried out using the colourimetric broth microdilution kit Sensititre YeastOne YO10. Biofilm-producing capability was evaluated by quantifying biomass formation spectrophotometrically following staining with crystal violet.
RESULTS: Twenty-four non-repetitive isolates of C. tropicalis were collected. The resistance rates to the triazole agents were 29.2% for fluconazole, 16.7% for itraconazole, 20.8% for voriconazole and 8.3% for posaconazole-the pan-azole resistance rate was identical to that of posaconazole. No resistance was recorded for amphotericin B, flucysosine or any of the echinocandins tested. A total of 16/24 (66.7%) isolates were categorized as high biomass producers and 8/24 (33.3%) were moderate biomass producers. None of our isolates were low biomass producers.
CONCLUSION: The C. tropicalis isolates from our centre were resistant only to triazole agents, with the highest resistance rate being recorded for fluconazole and the lowest for posaconazole. While this is not by itself alarming, the fact that our isolates were prolific biofilm producers means that even azole-susceptible isolates can be paradoxically refractory to antifungal therapy.
Fulltext A Preliminary Study on Coagulation Parameters and Sterility of Thawed Refrozen Fresh Frozen Plasma

Draman R, Yousuf R, Abdul Aziz S, Ding CH, Zainol S, Leong CF

Indian J Hematol Blood Transfus, 2020 Jan;36(1):112-116.
PMID: 32174694 DOI: 10.1007/s12288-019-01171-0

Thawed fresh frozen plasma (FFP) if not used within 6 h, may have to be discarded due to the risk of contamination and uncertainty about its quality. The main objective of this study was to evaluate the levels of coagulation Factor II (FII), Factor VIII (FVIII), fibrinogen and bacterial growth in thawed refrozen FFP. Thirty FFP samples were collected from healthy donors. FFP were thawed in water bath at 37 °C for 20-25 min. Approximately 10 mL of plasma from each FFP unit was tested for FII, FVIII, fibrinogen and sterility. The thawed FFP units were then kept at 4 °C for 6 h before being refrozen and stored at - 20 °C. Two weeks later, the refrozen FFP were thawed again and representative samples were analysed as before. There was a significant decline in the mean FVIII level, from 155.77% to 85.6% at second thaw. The mean FII level increased significantly from 74.9% to 82%, whereas the mean fibrinogen level fell from 3.34g/L to 3.28 g/L, but the decline was not statistically significant. There was no bacterial contamination in all samples at both time points. Refrozen plasma may be considered as an alternative to the storage of thawed unused FFP provided they are kept in a controlled environment to reduce wastage. These thawed refrozen FFP can be used later in bleeding cases like other FFP as the levels of FVIII are still within the standard haematology range (0.5-2 IU/mL) and above the minimal level of 30% coagulation factors required for adequate haemostasis.
Fulltext Seroprevalence of acute dengue in a Malaysian tertiary medical centre

Ding CH, Rashid ZZ, Rahman MM, Khang N, Low WN, Hussin N, et al.

Pak J Med Sci, 2016 Mar-Apr;32(2):495-8.
PMID: 27182269 DOI: 10.12669/pjms.322.9320

The aims of this study were to determine the seroprevalence of acute dengue in Universiti Kebangsaan Malaysia (UKM) Medical Centre and its correlation with selected haematological and biochemical parameters.