Implementation and expansion of laboratory capacity for molecular diagnostics in response to COVID-19 and preparedness for other emerging infectious diseases in the Islamic Emirate of Afghanistan

Background

Afghanistan experienced various outbreaks before and during the Covid-19 pandemic, including dengue, Crimean Congo hemorrhagic fever (CCHF), measles, and acute watery diarrhea (AWD). Diagnostic and surveillance support was limited, with only the Central Public Health Laboratory equipped to handle outbreak responses. This article highlights initiatives taken to improve diagnostic capabilities for COVID-19 and other outbreaks of public health concern encountered during the pandemic.

Background

The World Health Organization (WHO) Afghanistan Country Office collaborated with the WHO Eastern Mediterranean Regional Office (EMRO), Central Public Health Laboratory (CPHL), and National Influenza Center (NIC) to enhance COVID-19 diagnostic capacity at national and subnational facilities. To alleviate pressure on CPHL, a state-of-the-art laboratory was established at the National Infectious Disease Hospital (NIDH) in Kabul in 2021-2022, while WHO EMRO facilitated the regionalization of testing to subnational facilities for dengue, CCHF, and AWD in 2022-2023.

Results

COVID-19 testing capacity expanded nationwide to 34 Biosafety Level II labs, improving diagnosis time. Daily testing rose from 1000 in 2020 to 9200 in 2023, with 848,799 cumulative tests. NIDH identified 229 CCHF cases and 45 cases nationally. Dengue and CCHF testing, decentralized to Nangarhar and Kandahar labs, identified 338 dengue and 18 CCHF cases. AWD testing shifted to NIDH and five subnational facilities (Kandahar, Paktia, Balkh, Herat, and Nangarhar labs), while measles testing also decentralized to nine subnational facilities.

Conclusion

Afghanistan implemented a remarkable, multisectoral response to priority pathogens. The nation now possesses diagnostic expertise at national and subnational levels, supported by genomic surveillance. Future efforts should concentrate on expanding and sustaining this capacity to enhance public health responses.

Sex Differences in Proximal Thoracic Aortic Disease Pathology: A Call to Action

Introduction/Objective

Sex disparity is reported across all forms of cardiovascular diseases. Only few studies have focused on sex differences in thoracic aortic disease pathology. We aim to identify and understand sex differences in this patient group to bridge the knowledge gap and improve clinicopathologic outcomes.

Methods/Case Report

This is a retrospective analysis of 83 proximal thoracic aortic aneurysm and dissection (TAAD) cases treated at a single quaternary care center in 2019. Chart review was done for demographics. Consensus criteria (Stone JR et al. Cardiovasc Pathol 2015; 24:267-78; Halushka MK et al. Cardiovasc Pathol 2016; 25:247-57) and a scoring system (Waters KM et al. Cardiovasc Pathol 2017; 30:6-11) were used for pathology reporting. Clinical correlation was also made. Pearson’s chi-square test was used for statistical analysis.

Results (if a Case Study enter NA)

83 patients (61 male and 22 female) were retrieved. Overall thoracic aortopathy was higher among males, accounting for 73.4% of individuals with TAAD. In a subgroup analysis, there was no sex difference in dissection, aortic root involvement, and bicuspid aortic valve (p>0.05). Genetic aortopathy was more prevalent in females than males (27.2% vs 9.8%, p=0.04) alongside early age at first aortic event (median age: 31y vs 52y). Histopathologically, females had frequent translamellar mucoid extracellular matrix accumulation (45.4% vs 22.9%, p=0.04), extensive (54.5% vs 27.8%, p=0.02) and severe (59% vs 34.4%, p=0.04) elastic fiber fragmentation, higher band like (9% vs 6.5%, p>0.05) plus extensive (13.6% vs 4.9%, p>0.05) smooth muscle nuclei loss, and extensive (13.6% vs 1.6%, p=0.01) plus dense (4.5% vs 1.6%, p>0.05) laminar medial collapse than males.

Conclusion

In our patient population, females have a lower prevalence of thoracic aortic disease treated with open repair. However, those who develop TAAD harbor a greater burden of wall pathology and probable worse outcomes. We recommend sex-based analysis of all research on thoracic aortic diseases.

P2720Diagnostic accuracy of Quantitative Flow Ratio (QFR) and Vessel Fractional Flow Reserve (vFFR) compared to Fractional Flow Reserve (FFR) based on 7.5 frames/second coronary angiography

Background

Fractional flow reserve (FFR) is the gold standard for the physiological assessment of intermediate coronary artery lesions. Recently, several novel methods for computation of FFR based on 3-dimensional quantitative coronary angiography have been developed. These techniques allow analyses to be performed retrospectively and do not require induction of hyperaemia. The development and validation of these techniques are based on good quality coronary angiography with high frames per second (15 fps) acquisition. The diagnostic accuracy of Quantitative Flow Ratio (QFR) and Vessel Fractional Flow Reserve (vFFR) in real world “radiation-save mode” coronary angiography has not been studied.

Purpose

To validate the accuracy of QFR and vFFR compared to FFR based on a series of coronary angiography acquired at 7.5 fps.

Methods

We retrospectively analyzed 134 vessels (102 patients) with intermediate coronary artery stenosis (30–90%) in whom an FFR measurement had been performed. All the coronary angiography were acquired at 7.5 fps. 33 vessels (20 patients) were excluded from the study due to unsuitable coronary anatomy, invalid FFR measurements, poor image quality and lack of 2 projections ≥25° apart. A total of 101 vessels (82 patients) were included in the final analysis. Contrast-QFR (cQFR), fixed-QFR (fQFR) and vFFR analysis were performed in these vessels by two independent trained experts blinded to the FFR readings. FFR measurements at hyperaemic steady state was taken as the gold standard reference.

Results

Good intra- and inter-observer reliability was noted for fQFR, cQFR and vFFR analysis (intra-observer mean difference for fQFR: 0.016±0.060, p=0.066; cQFR: 0.009±0.053, p=0.230; vFFR: 0.008±0.040, p=0.175; inter-observer mean difference for fQFR: 0.001±0.036, p=0.847; cQFR: −0.001±0.049; p=0.910, vFFR: −0.005±0.037, p=0.393). fQFR and cQFR showed good correlation with FFR (r=0.694, p<0.001 and r=0.674, p<0.001, respectively) while vFFR showed moderate correlation with FFR (r=0.388, p<0.001). Similarly, fQFR and cQFR showed good accuracy for the detection of functionally significant coronary stenosis (fQFR AUC 0.882 (95% CI 0.803–0.938) and cQFR AUC 0.886 (95% CI 0.807–0.940)) while vFFR showed moderate accuracy with AUC 0.719 (95% CI 0.621–0.804). For identifying functionally significant stenosis (FFR ≤0.80), the overall diagnostic accuracy were 81.2%, 85.2%, 75.3% for fQFR, cQFR and vFFR, repectively. The sensitivity and specificity were 72.7%, 89.9% (fQFR); 83.5%, 31.8% (cQFR) and 68.2%, 87.3% (vFFR).

Conclusion

Functional assessment of intermediate coronary stenosis based on 7.5 fps angiography-derived computational modelling is feasible. Our study shows that fQFR and cQFR have a better diagnostic accuracy for detecting functionally significant coronary stenosis compared to vFFR. At the lower radiation-save mode 7.5 fps angiography, cQFR does not appear to provide additional diagnostic accuracy compared to fQFR.

Pathogenic FBN1 variants in familial thoracic aortic aneurysms and dissections

Marfan syndrome (MFS) due to mutations in FBN1 is a known cause of thoracic aortic aneurysms and acute aortic dissections (TAAD) associated with pleiotropic manifestations. Genetic predisposition to TAAD can also be inherited in families in the absence of syndromic features, termed familial TAAD (FTAAD), and several causative genes have been identified to date. FBN1 mutations can also be identified in FTAAD families, but the frequency of these mutations has not been established. We performed exome sequencing of 183 FTAAD families and identified pathogenic FBN1 variants in five (2.7%) of these families. We also identified eight additional FBN1 rare variants that could not be unequivocally classified as disease-causing in six families. FBN1 sequencing should be considered in individuals with FTAAD even without significant systemic features of MFS.

The reduction of dose in paediatric panoramic radiography: the impact of collimator height and programme selection

OBJECTIVES

The aim of this work was to estimate the doses to radiosensitive organs in the head of a young child undergoing panoramic radiography and to establish the effectiveness of a short collimator in reducing dose.

METHODS

Thermoluminescent dosemeters were used in a paediatric head phantom to simulate an examination on a 5-year-old child. The panoramic system used was an Instrumentarium OP200 D (Instrumentarium Dental, Tuusula, Finland). The collimator height options were 110 and 140 mm. Organ doses were measured using exposure programmes intended for use with adult and child size heads. The performance of the automatic exposure control (AEC) system was also assessed.

RESULTS

The short collimator reduced the dose to the brain and the eyes by 57% and 41%, respectively. The dose to the submandibular and sublingual glands increased by 32% and 20%, respectively, when using a programme with a narrower focal trough intended for a small jaw. The effective dose measured with the short collimator and paediatric programme was 7.7 μSv. The dose to the lens of the eye was 17 μGy. When used, the AEC system produced some asymmetry in the dose distribution across the head.

CONCLUSIONS

Panoramic systems when used to frequently image children should have programmes specifically designed for imaging small heads. There should be a shorter collimator available and programmes that deliver a reduced exposure time and allow reduction of tube current. Programme selection should also provide flexibility for focal trough size, shape and position to match the smaller head size.

[Acute hematogenous osteomyelitis of the obturator rim in seven children]

PURPOSE OF THE STUDY

Acute osteomyelitis of the rim of the obturator foramen is rarely reported. The clinical presentation is atypical, making diagnosis a difficult task. We report a series of seven cases of osteomyelitis of the obturator rim which illustrate the different features of this localization.

MATERIAL AND METHODS

The series included seven boys with osteomyelitis involving the obturator foramen. We reviewed the clinical history, the diagnostic approach and management. Complications and anatomic outcome were noted at mean three years follow-up (range one to 10 years).

RESULTS

Mean age was 9.5 years (five to 12 years). Bilateral involvement was noted in one boy. Mean time from symptom onset to consultation was five days and mean time from consultation to hospitalization was eight days. No specific clinical presentation could be identified. Fever was not a constant feature. Mean body temperature was 38.6 degrees C and was not greater than 38.5 degrees C in four children. Symptoms were limited to hip pain in five cases and abdominopelvic pain was noted in two. Physical examination failed to trigger exquisite ischial or pubic pain in two patients. The osteomyelitis involved the ischiopubic ramus in four cases, the ischium in two with one bilateral case, and the pubis in one. Certain diagnosis was established as follows: MRI findings plus isolation of the pathogenic agent (n=4) ; the plain x-ray showed a defect in the ischiopubic ramus, MRI showed signs favoring osteomyelitis of the ischiopubic ramus and surgery evacuated a purulent collection (n=1) ; strong uptake of the obturator rim on scintigraphy (n=2). Medical treatment was given in all cases and surgery was performed in six patients. Outcome was noted at three years follow-up, range one to 10 years. All patients recovered normal function. There were no complications.

DISCUSSION

Hematogenous osteomyelitis of the pelvis is exceptional (2-11 % of cases of osteomyelitis). Localization in the obturator rim is rare. We discuss the specific diagnostic and therapeutic features of this localization. Despite the controversy concerning the treatment of pelvic osteomyelitis and in particular cases involving the obturator rim, prognosis is generally good. No complications have been described in the literature specifically associated with osteomyelitis of the obturator rim.

[Acute hematogenous osteomyelitis of the neck of the femur in children: 28 cases]

PURPOSE OF THE STUDY

Osteomyelitis of the neck of the femur is uncommon, often with a misleading clinical presentation. We report a series of 28 cases of osteomyelitis of the femoral neck to illustrate the particular clinical and imaging findings related to this localization.

MATERIAL AND METHODS

This was a series of 28 children treated in our unit from 1990 through 2004: 17 boys and 11 girls, mean age eight years (range one month to 14 years). We analyzed the data in this series using a standard checklist, which noted the diagnostic and therapeutic measures. Results were analyzed by studying the complications, anatomic and functional outcome at mean follow-up of 3.5 years.

RESULTS

Time from symptom onset to consultation was five days on average with a delay of 4.5 days from consultation to hospitalization. Intense pain was noted for eight patients (28%) and total functional incapacity of the limb was noted for 15 (53%). Hip stiffness was observed in 11 patients (39%). The diagnosis of osteomyelitis of the femoral neck was established on the basis of imaging (MRI or scintigraphy) in three patients with bacteriological proof in two, of operative findings which confirmed the neck localization in 19, and on changes in the X-ray image of the neck in six. A positive bacteriology was noted in 71%. The germ was isolated from blood cultures and local samples obtained by arthrotomy in five patients (same germ), only in blood cultures for four, and only in local samples in 11. Met-S Staphylococcus aureus was isolated in 18 patients, Met-R S. aureus in one and a Streptococcus in one. All patients were given medical treatment and 25 underwent surgery. There were five thromboembolic complications and five patients who developed femoral pandiaphysitis. Results were analyzed at mean 3.5 years (range four months to 14 years). Complete hip motion was recovered in 78%. There were four cases of hip stiffness and two cases of ankylosis. Partial cephalic necrosis was noted in two hips and total necrosis of the head and neck in two.

DISCUSSION

Little data is available in the literature on isolated osteomyelitis of the femoral neck. Based on the pathogenic mechanisms known for osteomyelitis, an isolated localization in the neck of the femur, with no other site in the hip joint, is quite possible in an early stage of infection. We discuss the specific clinical and imaging features of this localization. Analysis of our findings show that the prognosis of femoral neck osteomyelitis is directly related to time to management. Outcome is poorer when treatment is started late. Prognosis is poor if pandiaphysitis develops.

Robinow syndrome: report of two cases and review of the literature

We report two patients with Robinow syndrome, review the published literature and stress the importance and limitations of radiographic examination in the diagnosis of this disorder, which shows extreme clinical and radiographic variability. The radiographic differential diagnosis of Robinow syndrome is discussed.

Fracture de l’ulna et luxation congénitale bilatérale de la tête radiale

We report a case of bilateral congenital dislocation of the radial head discovered at the time of a fracture of the ulna. The dislocation was missed initially and when considered as part of the Monteggia fracture, raised a problem concerning the therapeutic approach. The purpose of this report is the emphasize the importance of careful physical examination before undertaking treatment of any lesion.

[Nocardia farcinica brain abscess: clinical and specific radiological findings and management. Report of two cases in immunononcompromised patients]

Nocardia spp. cerebral abscesses are rare and usually occur in immunocompromised patients. We report two recent cases of cerebral abscesses due to Nocardia farcinica in immunocompetent patients and review the literature about diagnosis and therapeutic issues. Outcome was good for the two patients following an early identification of the bacteria. Stereotactic biopsy was performed in one case and craniotomy with excision of the abscess in the other case. In both cases, complete identification of the bacteria could be achieved, followed by prolonged antibiotic therapy. Exposure to the germ (mainly telluric) is often difficult to suspect from the past medical history of the patient. Diagnosis is also unexpected. Despite the typically and characteristic aspect on CT and MRI, specific identification and anti-microbial sensitivity profiles are necessary to optimize treatment. In some rare cases, unusual species like Nocardia farcinica, can be resistant to numerous antibiotics requiring adjustments of medical management. Early identification of the bacteria is necessary to achieve good outcome in immunocompetents patients.

[Spinal anesthesia in children: comparative study of hyperbaric bupivacaine with or without clonidine]

OBJECTIVE

To evaluate the effect of intrathecal clonidine in children.

STUDY DESIGN

A prospective randomised study.

PATIENTS AND METHODS

45 children, 6 to 15 years old, were randomised in two groups; receiving either 0.5% hyperbaric bupivacaine or 0.5% hyperbaric bupivacaine added to clonidine 2 micrograms.kg-1. We assessed quality and length of motor and sensory blocks and side effects of clonidine: hypotension, bradycardia and sedation.

RESULTS

Clonidine was associated with prolongation of motor block. 190 +/- 42 min vs 150 +/- 35 min (p < 0.01), but the difference was not significant. Postoperative analgesia was longer in clonidine group, 490 +/- 35 min vs 200 +/- 50 min (mean +/- SD), p < 0.001. Clonidine was associated with higher incidence of hypotension 54 vs 36% and bradycardia 30 vs 0%.

CONCLUSION

These data suggest that intrathecal clonidine 2 micrograms.kg-1 is associated with extending duration of postoperative analgesia but with moderate side effects.

Subcutaneous herniation of tendon interposition after trapeziectomy in three cases: explanation and implications

We report a complication following trapeziectomy and tendon interposition. Subcutaneous herniation of the tendon interposition occurred in 3 of 412 cases in which trapeziectomy, ligament reconstruction, and tendon interposition were performed. This herniation occurred posterolaterally in the early postoperative period and resulted in dorsal swelling and superficial pain. Magnetic resonance imaging was helpful in confirming the diagnosis and excision of the herniated interposition material resulted in satisfactory pain relief and functional outcome as long as metacarpal stability was present.

Molecular epidemiology of Mycobacterium tuberculosis strains isolated during a 3-year period (1993 to 1995) in Seville, Spain

The genetic polymorphism of Mycobacterium tuberculosis strains isolated in Seville, Spain, was studied by using computer-assisted analysis of the IS6110 fingerprint in order to determine the current situation and to evaluate the human-to-human transmission of this pathogen. One hundred seventy-six isolates from 175 patients among the 205 patients diagnosed with tuberculosis (TB) during a 3-year period (1993 to 1995) were cultured and analyzed. One hundred nine patients (62%) were infected with genetically different isolates, and 67 isolates (38%) were grouped into 19 clusters. These results demonstrate that the level of clustering of strains in Seville is intermediate between those in developed and developing countries. Epidemiological relatedness was shown for isolates from only 10 of these clusters. Active and high transmission rates exist in children and in human immunodeficiency virus (HIV)-infected adults, while in non-HIV-infected adults this transmission rate is moderate. Although transmission from children to adults is uncommon, the probability of transmission from HIV-infected patients to young adults not infected with HIV may be higher. On the basis of these observations, we predict a constant rise in the rate of TB transmission among HIV-infected patients and probably in young adult patients not infected with HIV if measures for the effective prevention of TB among the HIV-infected population are not implemented.

[False tuberculosis outbreak caused by specimen contamination in a micro-bacteriology laboratory: confirmation by molecular techniques]

BACKGROUND

The authors describe a false outbreak of tuberculosis by contamination in sample processing.

METHODS

The longitudinal polymorphisms of restriction fragments (RFLPs) of 6 strains of Mycobacterium tuberculosis isolated in different patients over a three week period and which were apparently implicated in an outbreak of tuberculosis were analyzed.

RESULTS

Four of the strains studied presented identical restriction pattern and the remaining two presented totally different patterns. Following study of the clinical histories and the epidemiologic relationships three cases of tuberculosis were confirmed. The other three strains isolated corresponded to contamination during the sampling process.

CONCLUSIONS

In a possible outbreak of six cases of tuberculosis, molecular techniques have allowed identification of three true cases of tuberculosis and have demonstrated contamination during the sampling process in three other cases. The latter could not have been shown with the clinical and phenotypical data of the strains.

Nosocomial transmission of tuberculosis infection in pediatrics wards

Analysis of restriction fragment length polymorphisms is a well-established method of "DNA fingerprinting" that has been used to trace the transmission of particular strains of Mycobacterium tuberculosis during investigations of outbreaks. This report describe the use of restriction fragment length polymorphisms and arbitrarily primed polymerase chain reaction analysis to investigate two outbreaks of tuberculosis that affected six children who attended two pediatric wards in our hospital. In both outbreaks a history of household exposure to an adult with M. tuberculosis was obtained and suspected tuberculous contacts were identified. We have demonstrated unequivocally the strain relationship among the isolates in all the cases by restriction fragment length polymorphisms and arbitrarily primed polymerase chain reaction analysis. These techniques are very useful for performing epidemiologic studies of tuberculosis in children where natural history of tuberculosis infection is different from that in adults in that it is almost always primary infection rather than reactivation.

Initial studies on the N-glucosylation of phenobarbital by mouse liver microsomes using a radiochemical high-performance liquid chromatographic (HPLC) method

A method is described for the assay of phenobarbital N-glucosylation using UDP-D-[6-3H]glucose. The radioactive phenobarbital N-glucoside conjugates [(5R)-PBG, (5S)-PBG] formed during the incubations were resolved from each other and from uncharacterized radioactive products by semipreparative HPLC. The product ratio of the N-glucosides of (5R)-PBG/(5S)-PBG was 2.9 for the crude liver homogenate and 3.0 +/- 0.5 for the microsomes. Magnesium was necessary for optimal activity. The Km values for formation of (5R)-PBG, (5S)-PBG, and (5R + 5S)-PBG were 1.55 +/- 0.35, 1.27 +/- 0.14, and 1.47 +/- 0.21 mM, respectively. The Vmax values for formation of (5R)-PBG, (5S)-PBG, and (5R + 5S)-PBG were 1.34 +/- 0.05 x 10(-6), 0.43 +/- 0.01 x 10(-6), and 1.77 +/- 0.04 x 10(-6) mumol/min/mg microsomal protein, respectively. It was observed that at concentrations greater than 5 mM sodium phenobarbital, inhibition of formation of phenobarbital N-glucosides occurred. The product ratio of (5R)-PBG/(5S)-PBG is comparable to that observed in the urinary excretion studies with the mouse and opposite to that observed in urinary excretion studies in humans.

Primary aortoduodenal fistula caused by Salmonella aortitis

We report the management and follow-up of two cases of primary aortoduodenal fistulas caused by Salmonella aortitis. The origin, presentation, diagnosis, and results of operative therapy for patients with primary aortoduodenal fistulas, especially patients with positive aortic wall cultures, are reviewed. Successful therapeutic principles included early intervention, primary duodenal repair, aneurysm resection, aortic reconstruction with an in situ Dacron graft, and prolonged courses of bactericidal antibiotics.

Clinical results of coronary bypass in 500 patients at least 10 years after operation

We determined the outcome of coronary artery bypass surgery in 500 consecutive patients followed for at least 10 years after operation. There were 446 males (89.2%). Angina pectoris was the major indication for operation. Four hundred six patients (81%) had multivessel coronary artery disease and 348 (69.9%) had good left ventricular function. At 10 years of follow-up, 48% of patients were asymptomatic and 41% were improved. Propranolol was being used by 36% of patients and nitrates by 49%. Of the 355 patients younger than 65 years of age at the time of follow-up, 57% were employed full time and 24% were working part-time. Reoperation was performed in 9% of patients. Analysis of survival by Kaplan-Meier curves indicated that overall 10-year survival rates were 78% for one-vessel disease, 69% for two-vessel disease, 48% for three-vessel disease and 67% for left main coronary artery disease. For patients with good left ventricular function, the 10-year survival rates were 83% for one-vessel disease, 73% for two-vessel disease, 53% for three-vessel disease and 73% for left main disease. For patients with poor left ventricular function, the rates were 56%, 59%, 40% and 54%, respectively. Cox multivariate analysis indicated that preoperative diuretic use, history of heart failure, the number of diseased vessels, and infarct on the preoperative ECG were all good predictors of survival. This study shows that the outcome of coronary artery bypass surgery 10 years operation is highly favorable.