Effectiveness of COVID-19 diagnosis and management tools: A review.

OBJECTIVE: To review the available literature concerning the effectiveness of the COVID-19 diagnostic tools. BACKGROUND: With the absence of specific treatment/vaccines for the coronavirus COVID-19, the most appropriate approach to control this infection is to quarantine people and isolate symptomatic people and suspected or infected cases. Although real-time reverse transcription-polymerase chain reaction (RT-PCR) assay is considered the first tool to make a definitive diagnosis of COVID-19 disease, the high false negative rate, low sensitivity, limited supplies and strict requirements for laboratory settings might delay accurate diagnosis. Computed tomography (CT) has been reported as an important tool to identify and investigate suspected patients with COVID-19 disease at early stage. KEY FINDINGS: RT-PCR shows low sensitivity (60-71%) in diagnosing patients with COVID-19 infection compared to the CT chest. Several studies reported that chest CT scans show typical imaging features in all patients with COVID-19. This high sensitivity and initial presentation in CT chest can be helpful in rectifying false negative results obtained from RT-PCR. As COVID-19 has similar manifestations to other pneumonia diseases, artificial intelligence (AI) might help radiologists to differentiate COVID-19 from other pneumonia diseases. CONCLUSION: Although CT scan is a powerful tool in COVID-19 diagnosis, it is not sufficient to detect COVID-19 alone due to the low specificity (25%), and challenges that radiologists might face in differentiating COVID-19 from other viral pneumonia on chest CT scans. AI might help radiologists to differentiate COVID-19 from other pneumonia diseases. IMPLICATION FOR PRACTICE: Both RT-PCR and CT tests together would increase sensitivity and improve quarantine efficacy, an impact neither could achieve alone.

Optimal abdominal CT protocol for obese patients.

INTRODUCTION: This study investigated the impact of different protocols on radiation dose and image quality for obese patients undergoing abdominal CT examinations. METHODS: Five abdominal/pelvis CT protocols employed across three scanners from a single manufacturer in a single centre used a variety of parameters (kV: 100/120, reference mAs: 150/190/218/250/300, image reconstruction: filtered back projection (FBP)/iterative (IR)). The routine protocol employed 300 reference mAs and 120 kV. Data sets resulting from obese patient examinations (n = 42) were assessed for image quality using visual grading analysis by three experienced radiologists. Objective assessment (noise, signal/contrast-noise ratios) and radiation dose was compared to determine optimal protocols for prospective testing on a further sample of patients (n = 47) for scanners using FBP and IR techniques. RESULTS: Compared to the routine protocol, mean radiation dose was reduced by 60% when using 100 kV and SAFIRE technique strength 3 (p = 0.001). Reduction of up to 30% in radiation dose was noted for the FBP protocol: 120 kV and 190 reference mAs (p = 0.008). Subjective and objective image quality for both protocols were comparable to that of the routine protocol (p > 0.05). An overall improvement in image quality with increasing strength of SAFIRE was noted. Upon clinical implementation of the optimal dose protocols, local radiology consensus deemed image quality to be acceptable for the participating obese patient cohort. CONCLUSION: Radiation dose for obese patients can be optimised whilst maintaining image quality. Where iterative reconstruction is available relatively low kV and quality reference mAs are also viable for imaging obese patients at 30-60% lower radiation doses.

Circulating markers of oxidative stress and liver fibrosis in Sudanese subjects at risk of schistosomiasis and hepatitis.

Epidemiological studies in the developing world are frequently biased by the simultaneous presence of several infectious pathogens. In the present study, we examined the usefulness of circulating markers of oxidative stress and liver fibrosis to investigate the distinct forms of chronic liver inflammations associated with schistosomiasis and viral hepatitis, respectively. The study was performed in a Sudanese population exposed to Schistosoma. Circulating hyaluronic acid (HA) was used as a marker of liver fibrosis; the severity of schistosomiasis was determined by ultrasonic examination; viral hepatitis infection was ascertained by circulating anti-hepatitis antibodies. Serum markers were examined also in Sudanese subjects not exposed to Schistosoma infection and in French control subjects. We found a drastic decrease of lycopene levels in the subjects exposed to schistosomiasis in comparison with non-exposed Sudanese and French control subjects. Retinol, alpha-tocopherol and five carotenoids were unchanged. Lycopene depletion was unlikely to be due to variations of nutritional origin, since the lycopene/beta-carotene ratio was five-fold lower in the population at risk of schistosomiasis than in the other groups. We found that high HA serum levels were associated with severe periportal fibrosis but not with viral infection. Conversely, levels of the oxidized lipid malondialdehyde (MDA) were associated with viral infection but not with the severity of schistosomiasis, even though the two infections had additive effects. We concluded that serum markers are valuable tools for investigating the complex effects of co-existing factors of chronic liver inflammation.

Evolution of metronidazole and tetracycline susceptibility pattern in Helicobacter pylori at a hospital in Saudi Arabia.

The association of Helicobacter pylori with chronic gastritis and peptic ulcer disease led to new therapeutic approaches including the use of antibiotics. Recently, resistance of H. pylori to antibiotics has emerged as the major cause of treatment failure. This retrospective analysis was aimed at investigating the development of antimicrobial susceptibility patterns amongst H. pylori strains isolated at King Fahd Hospital of the University, Al-Khobar. Susceptibility patterns obtained using isolates from a pilot study (1987-1988) were compared with those subsequently isolated (1990-1996). Metronidazole resistance was estimated to be 35.2% in the first period but more than doubled (78.5%) during the second period. Isolates from females showed a higher resistance rate to metronidazole than those from males. Only one strain was tetracycline resistant. The extremely high resistance rate to metronidazole indicates that it may not be very effective for eradication of H. pylori. Tetracycline should prove a useful component of treatment regimens in this geographical region.

Seroepidemiological study of Toxoplasma gondii infection in the human population in the Eastern Region.

OBJECTIVE: Toxoplasma gondii is an an obligate intracellular protozoan parasite that causes toxoplasmosis. The infection is worldwide, particularly in warm and moist climates. Few studies have been conducted on the prevalence of subclinical or overt disease in Saudi Arabia. No population-based study was conducted or the seroprevalence of toxoplasmosis in humans in Saudi Arabia and this initiated the present study. The present study aimed at studying seroprevalence of Toxoplasma IgG and IgM antibodies in sera from 5 areas in the Eastern Region of Saudi Arabia. METHODS: A population based epidemiological approach, prevalence according to lifestyle (urban or rural), gender (male or female) occupation and age. RESULTS: Inactive toxoplasmosis (IgG levels) is of rather high prevalence in the human population in the Eastern Region of Saudi Arabia (25%). On the other hand, active toxoplasmosis (acquired during pregnancy) is of rather low prevalence in this study (5%). Active toxoplasmosis (IgM levels) is positively related to the level of exposure, high in farmers and employees in village rural areas and low in children and students in urban areas. CONCLUSION: Patients with active toxoplasmosis are to be treated and made aware of their situation. Hygienic conditions in areas of rather high prevalence of active toxoplasmosis are to be more strictly imposed to minimize transmission of the disease.

Sero-prevalence of toxoplasmosis in pregnant mothers and new born infants in eastern province, saudi arabia.

BACKGROUND: Toxoplasma gondii is an obligate intracellular protozoa of worldwide distribution. In immunocompetent adults, it is usually the cause of asymptomatic infection. However, infection during pregnancy poses a special risk because of the teratogenic effect of toxoplasma. OBJECTIVE: Determine the sero-prevalence of toxoplasmosis in pregnant women and newborn infants in King Fahd Hospital of the University, Al-Khobar, Eastern Province. METHODS: In this hospital-based study, sera from 175 pregnant females were screened for toxoplasma IgG and IgM. RESULTS AND CONCLUSION: A very low number (N=1/175, 0.57%) of pregnant mothers seroconverted during pregnancy, although many (N=69/175, 39.4%) were recorded with inactive toxoplasmosis during pregnancy. Delivery was normal in all cases except for a small number (N=1/175, 0.57%) of newborns (as recorded from cord blood) who were positive for toxoplasmosis.

Dissemination in cutaneous leishmaniasis due to Leishmania major in different ethnic groups in Saudi Arabia.

BACKGROUND: Dissemination in patients with cutaneous leishmaniasis has previously been recorded in human infection with Leishmania major and L. tropica. In this study, the potential for dissemination in different ethnic groups in Saudi Arabia was compared. METHODS: The data were recorded from a group of 73 patients with suspected cutaneous leishmaniasis (43 Saudi and 30 non-Saudi) attending the Dermatology Clinics at King Fahd Hospital of the University and Al-Khobar Government Hospital at Al-Khobar, Eastern Region of Saudi Arabia. The patients were of various age groups (all male) between 1 and 55 years. The diagnosis of cutaneous leishmaniasis was confirmed clinically and by smear and skin biopsy. The following data were recorded for each patient: type, number, and anatomic sites of disseminative lesions and the frequency of co-occurrence of more than one type of lesion. RESULTS: Three types of disseminative lesions due to zoonotic cutaneous leishmaniasis were recorded in 16 patients (21.92%): subcutaneous nodules, satellite papules, and subcutaneous induration. The percentage of disseminative lesions in non-Saudi patients (36.66%) was higher than in Saudi patients (11. 63%). This was also true for the number of lesions: a mean of 12.27+/- 10 and 6.4+/-3, respectively. The coexistence of more than one type of disseminative lesion was higher in non-Saudi patients (63. 63%) than in Saudi patients (20.0%), as well as the occurrence of lesions on more than one body site: 36.4% in non-Saudi patients and 20.0% in Saudi patients. CONCLUSIONS: The potential for dissemination due to cutaneous leishmaniasis was significantly higher in the nonindigenous population than in the indigenous population in Saudi Arabia. Disseminative lesions must be clinically differentiated from other skin diseases and appropriately treated by avoiding the use of intralesional drugs or physical therapy.

Evaluation of PCR, culture and serology for the diagnosis of acute human brucellosis.

BACKGROUND: The diagnosis of brucellosis is frequently difficult to establish. This is not only because clinically, the disease can mimic any infectious and noninfectious disease, but also because the established diagnostic methods are not always successful. In this study, we have tried to evaluate PCR techniques in the diagnosis of brucellosis in comparison to conventional techniques. PATIENTS AND METHODS: Fifty peripheral blood samples from the following groups were collected: patients with brucellosis (17); patients with febrile illnesses due to factors other than brucella etiology (19); symptomatic occupationally exposed persons (9); and healthy volunteers (5). The last three groups were considered controls. Among the 17 Brucella samples, only 14 were obtained before treatment was begun. The samples were tested by serology, using the standard tube agglutination method (STA), blood culture using Bactec machines, and PCR using primer pair to amplify a 223-bp region within a gene coding for a 31-kD Brucella antigen. Diagnosis of brucellosis was based on compatible clinical picture in addition to positive blood culture and/or positive serology. RESULTS: Of the 17 blood samples from patients with brucellosis, eight were culture positive for Brucella species, and all showed high titer antibrucella antibodies. Only 14 of them were positive by PCR, and these were the samples submitted before initiation of therapy, representing 100% sensitivity. Among the 33 controls, blood culture was negative for Brucella in all of them, while one sample showed high-titer antibrucella antibodies. The latter was from the febrile illnesses group. PCR-based assay was able to detect four bands in the controls, all of which were from the occupationally exposed asymptomatic group. CONCLUSION: In view of the several advantages of PCR over the conventional methods for the diagnosis of brucellosis, such as speed, safety, high sensitivity and specificity, the technique might be considered for laboratory diagnosis of brucellosis. However, for the evaluation of asymptomatic highly exposed persons, PCR might be considered complementary to the traditional methods and followed up by serology and/or culture.

Continuing medical education on infectious diseases: a saudi university hospital experience.

BACKGROUND: Continuing medical education (CME) is an important and useful activity for updating knowledge in order to improve for outcome of health care. A CME update symposium on Infectious Diseases was therefore organized at the King Fahd Hospital of the University (KFHU), Al-Khobar, Saudi Arabia. Participants included clinicians, laboratory personnel and nursing staff from different hospitals and universities in Saudi Arabia. OBJECTIVES: To report the proceedings of the first CME on Infectious Diseases in the region and to evaluate it using a questionnaire-based feedback. METHODOLOGY: This CME was evaluated on specific feedback obtained on standardized evaluation forms provided during the symposium. The responses of 194 participants were statistically analyzed for the various components of the symposium. RESULTS AND CONCLUSION: Salient important issues covered during the program are presented. The CME included five sessions on: hospital acquired infections, immunology, mycotic diseases, malaria, lesihmaniasis and virology. Some lacunae were also identified. The evaluation of the scientific sessions showed a satisfaction level of 3.98 ± 0.59, on a scale of five. As this CME activity proved successful on many counts, it was concluded that it was worthwhile to conduct updates on infectious diseases on a regular basis.