Nature of Complex Network of Dengue Epidemic as a Scale-Free Network / 대한의료정보학회지

OBJECTIVES: Dengue epidemic is a dynamic and complex phenomenon that has gained considerable attention due to its injurious effects. The focus of this study is to statically analyze the nature of the dengue epidemic network in terms of whether it follows the features of a scale-free network or a random network. METHODS: A multifarious network of Aedes aegypti is addressed keeping the viewpoint of a complex system and modelled as a network. The dengue network has been transformed into a one-mode network from a two-mode network by utilizing projection methods. Furthermore, three network features have been analyzed, the power-law, clustering coefficient, and network visualization. In addition, five methods have been applied to calculate the global clustering coefficient. RESULTS: It has been observed that dengue epidemic follows a power-law, with the value of its exponent γ = −2.1. The value of the clustering coefficient is high for dengue cases, as weight of links. The minimum method showed the highest value among the methods used to calculate the coefficient. Network visualization showed the main areas. Moreover, the dengue situation did not remain the same throughout the observed period. CONCLUSIONS: The results showed that the network topology exhibits the features of a scale-free network instead of a random network. Focal hubs are highlighted and the critical period is found. Outcomes are important for the researchers, health officials, and policy makers who deal with arbovirus epidemic diseases. Zika virus and Chikungunya virus can also be modelled and analyzed in this manner.

Acute parapharyngeal abscess secondary to streptococcal mastoiditis

A rare case of parapharyngeal abscess caused by Streptococcus pneumoniae presenting as neck abscess is reported. The patient had 20 days history of cough, fever and swelling behind right ear. He had not responded to multiple antibiotic treatments given earlier. On the basis of clinical examination and CT scan finding, he was diagnosed as having parapharyngeal abscess pointing in the neck. The abscess was drained and the patient was treated with injectable Ceftriaxone, due to identification of penicillin - resistant Streptococcus pneumoniae

Catheter associated urinary tract infections in the intensive care unit of tertiary care hospitals: bacterial spectrum and their susceptibility pattern

To determine microbial spectrum of catheter associated urinary tract infection and their antimicrobial susceptibility pattern in patients under intensive care. This is a descriptive and cross-sectional study, which was carried out at the Department of Microbiology Armed Forces Institute of Pathology, Rawalpindi. This institute is providing laboratory cover to two tertiary care hospital and five institutes of excellence. A total of 122 isolates, obtained from urine of 100 catheterized patients, at Armed Forces Institute of Pathology, Rawalpindi for a period of six months were included in the study. Identification was carried out by biochemical and serological profile of the organism. The antimicrobial susceptibility tests of isolated organisms were performed by standard disk diffusion method as recommend by Clinical Laboratory Standards Institute. Majority [68%] of the organisms isolated were Gram negative organisms while 32% of the infections were due to Gram positive organisms/fungi. Moxifloxacin [86.40%] and imipenem [83.30%] were the most active antibiotics. Resistance was very high to ampicillin [88.50%] and trimethoprim /sulfamethoxazole [75.00%]. Majority of the catheter associated urinary tract infections are due to Gram negative but Gram positive organisms and fungi are also causing UTIs in about one third cases. Resistance to the conventional antimicrobials used for UTI was high

Lupus nephritis in children

To determine the clinicopathological pattern of lupus nephritis in paediatric nephrology patients. Case series study. The department of paediatric nephrology at the Children's Hospital and Institute of Child Health, Lahore, Pakistan, over a period of five years from January 2001 to December 2005. Twenty six patients upto the age 16 years of either gender, with a mean age of 12.4 _ 1.90 years having primary SLE with renal involvement in the form of oedema, hypertension, haematuria and proteinuria were included. Twenty one were females. Percutaneous renal biopsy was performed. Histological lesion was classified according to WHO classification. Patients were treated with immunosuppressive therapy and their clinical course was followed for at least one year. The mean duration of follow up was 1.77 years. Renal involvement was seen in 92.30% within 2 years of the onset of primary disease. Diffuse proliferative glomerulonephritis was the commonest histological lesion [n=14] followed by membranous nephropathy [n=6]. The commonest clinical manifestation was oedema [80.76%] followed by hypertension [46.15%]. Proteinuria was present in 100% of cases, haematuria in 38.46% and azotemia in 19.33% of patients. Nephrotic range proteinuria was more common in class III and IV, while azotemia was observed only in class IV. The disease was well controlled in 73.07%, relapse was seen in 3.8% of patients, 15.38% died of infections and uremic encephalopathy while 7.69% were lost to follow-up. Diffuse proliferative glomerulonephritis is the commonest histological lesion in our set-up. Renal involvement is mostly seen within first two years of the primary disease which can be controlled satisfactorily with immunosuppressive therapy

Nocardia canaliculitis presenting as pouted punctum

A rare case of culture-positive Nocardia canaliculitis is reported that presented with a history of chronic conjunctivitis and epiphora for the last 1.4 years, refractory to multiple treatment courses. Chronic conjunctivitis and a pouted punctum were observed in the right lower eyelid. Probing and sac syringing was performed. The "Sulfur granules" were expressed and subjected to various microbiological analyses. Nocardia sp was grown on culture. The patient was successfully managed with surgical removal of concretions and topical/systemic antibiotics

Methicillin resistant staphylococcus aureus prevalence amongst community versus hospital acquired skin and soft tissue infections

Methicillin resistant Staphylococcus aureus [MRSA] is becoming increasingly prevalent, not only in the hospital acquired but also the community acquired infections. Skin and soft tissues are a few of the important targets for this pathogen. A study was conducted at the departments of surgery, dermatology and pathology, Combined Military Hospital, Gujranwala Cantt to know the prevalence of MRSA amongst community vs. hospital acquired skin and soft tissue infections [SSTIs]. A total of 216 community acquired and 48 hospital acquired SSTIs were included in the study. The pus swabs/pus specimens collected from all the cases were processed for routine cultures. Isolates were identified as Staphylococcus aureus and resistance to methicillin was detected using standard techniques. Staphylococcus aureus was isolated in 64.35% of the community acquired and 72.91% of the hospital acquired SSTIs. Prevalence of MRSA amongst community acquired SSTIs was 26.6% while in the hospital acquired SSTIs was 68.57%. The study indicates quite a high prevalence of MRSA amongst community acquired and a very high prevalence in hospital acquired SSTIs. Further large scale studies are required to monitor the prevalence and spread of MRSA amongst SSTIs

Diagnostic role of EEG in children having unprovoked seizures, experience at the neurophysiology department, The children's hospital, Lahore

Although advances in imaging technology offer ever-increasing diagnostic accuracy, the electroencephalogram [EEG] retains its importance and is the cornerstone for the diagnosis and treatment of epilepsy. A cross-sectional descriptive study was conducted at Neurophysiology Department of The Children's Hospital, Lahore. Our aims were to find out the different types of epilepsies diagnosed on EEG in children referred for interictal EEG with recent clinical diagnosis of epilepsy. Out of 645 children referred for EEG after seizures, 415 [64%] were males and 230 [36%] were females, 21% had their first seizure before one year of age, 54% of them were between the ages of 1-5 years and 46% of them were more than 5 years of age. We found normal interictal EEGs in 54% whereas 46% children had abnormal EEGs. So in addition to supporting the diagnosis of epilepsy, EEG has significant potential to classify epileptic seizures

Early predictors of intractable epilepsy in children: a case control study

Case control, Hospital based. Site: Epilepsy Centre, The Children's Hospital, Lahore-Pakistan. From 1st Sept 05 to 30th Nov 06 Knowing the prognosis of epilepsy in children would undoubtly influence the treatment strategy. All the children, age 1 year to 16 years receiving anti-epileptic drugs for their idiopathic or cryptogenic epilepsy were the study population. After six months of commencement of treatment various factors associated with well control the ["controls"] and intractability the ["cases"] were analyzed and a univariate comparison was done between various factors for these two groups. Over a period of 14 months, 520 children, 33% the "control" and 67% the "cases" among these patients were enrolled for this study. Statistically, male gender history of birth asphyxia, initial seizure type, past head trauma, previous CNS infection and family history of epilepsy are not the risk factors, whereas seizures starting in infancy, seizures episodes >10 before commencing treatment, neonatal seizures and neurological deficit present at presentation were the risk factors for intractable epilepsy. Myoclonic seizures, status epilepticus before starting treatment and infantile spasm were seen in the "case" group only. We conclude children having risk factors for intractable epilepsy have poor prognosis and recommend that such children should be referred to epilepsy centre as soon as possible

Histiocytosis in children: Five years experience at a tertiary care hospital

Histocytosis is a diverse group of illness of monocyte- macrophage cell lineage. Diagnostic criteria and management protocols are not precisely defined due to cases. Study was conducted to review the clinical features at admission and outcome of histiocytosis following chemotherapy [DALHAX 83 protocol was used]. It was a retrospective study, carried out from March 2000 to February 2005, at department of hematology- oncology, The Children's Hospital and the Institute of Child Health, Lahore. From 01-03-2000 to 28-02-2005, total 36 cases with histocytosis disorders were admitted. It comprises 2% of total admissions, class 1 langerhan cell disease was the most common [24/36], followed by class II [8/36] and class III [4/36] cases among this group of illness. Fever and hepatosplenomegaly was present in all classes. Soft tissue swelling, jaundice and lymphadneopathy were also seen in class I, II and III histiocytosis respectively. Nineteen patients died/ left treatment and absconded with incomplete treatment. Seventeen patients responded to chemotherapy again. Histiocytosis class I is a chemosensitive disease. If the functional deterioration of the involved organ has not set in, class I disease has good prognosis

Gastroenteritis related to Pseudomonas aeruginosa: an outbreak

Thirty-eight soldiers with a few hours history of vomiting and loose motions were admitted at Pak Fd Level II hospital, United Nations Mission in Liberia, on 3rd May 2004. The illness started with vomiting which was followed by diarrhea. Seven had severe dehydration on admission. The stools were initially loose but became blood mixed in about 12 hours. The patients were managed with IV fluids and injectable antibiotics. In the next 48 hours, the frequency of stools decreased and the colour of stools changed to green. On culture, predominant growth of Pseudomonas aeruginosa was obtained from majority of the stool specimens. The isolate was sensitive to ciprofloxacin, the antibiotic being used for treatment of the cases. The patients became completely asymptomatic in next 3-5 days. On investigation it was found that all the individuals had taken their lunch about 5-6 hours back. They had taken 'langer' cooked food of 'daal' and 'chapatti'. The samples of left over food and water were collected for cultures. A similar isolate of Pseudomonas aeruginosa was found in the water consumed. The water was being brought from a nearby lake for washingtbathing purpose and was accidentally consumed for drinking on that day

Thrombocytopenia: a predictor of malaria among febrile patients in Liberia

The study was conducted to evaluate thrombocytopenia as a predictor for the diagnosis of malaria in febrile patients. Design: Retrospective, descriptive Place and duration of study: The study was conducted at Pakistan Field Level II hospital of United Nations Mission in Liberia during a period extending from March to November 2004. A total of 503 consecutive febrile patients were included in the study. Platelet counts were performed on automated hematology analyzer. Blood smears for malarial parasite were examined by experienced technicians. A total of 145 patients were diagnosed to have Plasmodium falciparum malaria. Out of these 109 [75.18%] had thrombocytopenia. The platelet count was normal in 77.09% of the malarial parasite negative febrile patients. The sensitivity of the platelet count considered as a predictor of malaria was 80.11% while specificity was 81.36%. The positive predictive value was 63.87% and the negative predictive value was 90.86%. Thrombocytopenia is a predictor of falciparum malaria in febrile patients in Liberia. Peripheral blood smears of febrile, thrombocytopenic patients should be carefully examined for the presence of malarial parasites in endemic areas. Key words Thrombocytopenia, Malaria, Plasmodium falciparum

Pattern of systemic fungal infections and antimicrobial susceptibility of isolates in cancer patients

Fungal pathogens are implicated as an important cause of morbidity and mortality in cancer patients. In Pakistan the pattern of systemic fungal infections in cancer patients is not known. The present study was done to determine the pattern of systemic fungal infections and antimicrobial susceptibility of fungal isolates in cancer patients in Rawalpindi. It is a non-interventional descriptive study carried out from May to October 2003 at the Armed Forces Institute of Pathology, Rawalpindi. Blood, urine, stool and sputum specimens were collected for culture isolation of fungi from 73 febrile cancer patients. Antifungal susceptibility of the isolates to amphotericin B, fluconazole and itraconazole was determined by Etest and broth macrodilution technique. Forty-five fungi were isolated from 28 patients. Twenty isolates were Candida albicans, 21 were non-Candida albicans yeasts: C. tropicalis [n=13], C. glabrata [n=5], C. kefyr [n=3], Rhodotorula rubra [n=1] and three were Aspergillus fumigatus. All the isolates of C. albicans were susceptible to itraconazole; one was resistant to fluconazole while 3 isolates showed intermediate resistance to amphotericin B. The non-Candida albicans were generally more resistant: all the isolates of C. kefyr were resistant to amphotericin B, two isolates of C. tropicalis were resistant to fluconazole and three isolates of C. glabrata were resistant to itraconazole. Isolates of A. fumigatus were susceptible to amphotericin B but resistant to fluconazole. Systemic fungal infections in cancer patients by non-Candida albicans are on the rise and they are generally more resistant than C. albicans. Antifungal susceptibility testing must be performed in these cases in order to improve survival and decrease morbidity. Itraconazole can be used for prophylaxis of fungal infections in these patients

Combined Schistosoma mansoni and Schistosoma haematobium infection

An imported case of combined Schistosoma mansoni and Schistosoma haematobium infection occurring in Liberia is reported. A young girl of 15 years, who had recently returned from the neighbouring country of Guinea, presented with 04 months history of passing blood in stools. Schistosoma mansoni ova were found in stool and Schistosoma haematobium ova in urine. She was treated with tablet praziquantel. She became symptom-free in four weeks and the number of ova passed in stool and urine decreased

Bloodstream infections in febrile neutropenic patients: bacterial spectrum and antimicrobial susceptibility pattern

Background: Bacterial infections are the major cause of morbidity and mortality among neutropenic patients. Prompt administration of empiric antimicrobial therapy for febrile neutropenic patients is considered vital. Before putting neutropenic patients on empiric antimicrobial regimens, it is essential to be aware of the spectrum of locally prevalent pathogens and their susceptibility pattern

Methods: We studied the bacterial spectrum and antimicrobial susceptibility pattern of organisms causing bloodstream infections in febrile neutropenic patients in Armed Forces Bone Marrow Transplant Centre, Rawalpindi and the Department of Oncology, Combined Military Hospital, Rawalpindi over a period of nine months from January to September 2002

Results: Blood specimens for culture and susceptibility testing were collected from 158 febrile patients with neutropenia. Eighty-three organisms were isolated from 60 patients. Thirty-six [43%] isolates were Gram-positive cocci and forty-seven [57%] were Gram-negative rods. Among the Gram-positive cocci, coagulase negative staphylococci [CoNS] were the predominant pathogens [26%], followed by Staphylococcus aureus [8%]. Among Gram-negative rods, Escherichia coli was the predominant isolate [13%] followed by Klebsiella pneumonia [10%], Acinetobacter johnsonii [10%] and Pseudomonas aeruginosa [7%]. Nine specimens yielded polymicrobial growth. Forty percent of Staphylococcus aureus and 55% of CoNS were resistant to methicillin. All the Gram-positive isolates were susceptible to vancomycin and teicoplanin. Among the Gram-negative rods, there was 100% resistance to ampicillin, 65% to gentamicin, 47% to amikacin and 66% to third generation cephalosporins. All the gram-negative isolates were susceptible to imipenem

Conclusion: The spectrum of isolates among febrile neutropenic patients in our population appears to be shifting towards Gram-positive microorganisms. Due to increasing levels of drug resistance among the isolates, a glycopeptide in combination with a carbapenem would be a prudent choice as empiric therapy in high-risk cases

Genus and species-specific IgG and IgM antibodies for pulmonary tuberculosis

To evaluate three different enzyme immunoassays for serological diagnosis of pulmonary tuberculosis and to compare their diagnostic accuracy in different combinations. Design: A non-interventional comparative study. Place and Duration of Study: The study was carried out at the Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi between April and September 2001. Subjects and Sera from patients suffering from pulmonary tuberculosis [n=94] with sputum positive for acid fast bacilli [AFB] and sera from control group of healthy individuals [n=90] with sputum negative for AFB were tested by Pathozyme-Myco G EIA, Pathozyme-TB Complex Plus EIA and Pathozyme Myco M EIA kits for the genus-specific IgG and IgM, and the species-specific IgG antibodies against antigens of Mycobacterium tuberculosis. The detection of IgG against genus-specific antigens by Pathozyme-Myco G had a sensitivity of 46% and a specificity of 93%, of IgG against species-specific antigens by Pathozyme-TB Complex Plus had a sensitivity of 64% and specificity of 97% and of IgM against genus-specific antigens by Pathozyme Myco M had a sensitivity of 67% and specificity of 98%. When the results of these immunoassays were evaluated in combination, their sensitivity improved. Combination of genus-specific IgM and species-specific IgG yielded best results with a sensitivity of 87% and specificity of 93%. The sensitivity of serological diagnosis of tuberculosis is low, but it can be increased by utilizing a combination of several antigens