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Biomedical subjects

S Naraqi

Publications and source records attributed to S Naraqi.

At least 91 records · Page 5Linked to original sources

Prospective study of prevalence, incidence, and source of herpesvirus infections in patients with renal allografts.

The prevalence, incidence, and source of infections with different types of herpesviruses were determined prospectively for 25 persons undergoing hemodialysis, 30 allograft recipients, and 16 kidney donors. The prevalence of prior infections with cytomegalovirus (CMV), herpes simplex virus (HSV), and Epstein-Barr virus (EBV) was high (72%-100%) and was similar for healthy persons and those with renal failure. The incidence of infections in patients undergoing hemodialysis was no greater than that before dialysis. In allograft recipients, the incidence of infection with CMV was 73%; HSV, 57%; EBV, 30%; and varicella-zoster virus (clinical), 7%. Ninety-seven percent of the patients developed an infection with one or more herpesviruses. Transfusions, hemodialysis, the allograft, and hospital environment were not significant sources in transmission. Uremia and splenectomy were unimportant in the reactivation of infection. Immunosuppressive drugs possibly algmented by a graft rejection response account for the high incidence of recrudescent infections with CMV and HSV.

Adult↗

Viremia with herpes simplex type 1 in adults. Four nonfatal cases, one with features of chicken pox.

Recovery of herpes simplex virus (HSV) Type 1 from the blood buffy coat of four adults is reported for the first time. All of the patients had vesicular stomatitis and facial vesicles; two also had either keratoconjunctivitis or disseminated skin lesions. The infection was not the primary one with HSV in any of them. Two of three patients who had renal failure were receiving immunosuppressive drugs; one patient was normal except for alcoholism and diabetes. None developed signs of visceral organ infection and all recovered within 2 to 4 weeks. The findings demonstrate the occurrence of heretofore unrecognized nonfatal HSV Type 1 viremia in both healthy and immunosuppressed leukocytes, can occur regardless of the presence of serum antibody, and may or may not be associated with the disseminated lesions.

Adult↗

Acute meningococcal pericarditis without meningitis.

Meningococcla pericarditis without evidence of meningitis of pericardial effusion in an 18-year-old man was cured following a ten-day course of orally administered ampicillin. Acute pericarditis resembling benign or viral pericarditis amy rarely be due to N meningitidis.

Acute Disease↗

Ataxia in patients infected with Salmonella typhi phage type D2: clinical, biochemical and immunohistochemical studies.

Reversible cerebellar dysfunction has been described in association with typhoid fever by a number of authors. Ataxia and tremors are relatively common manifestations of typhoid fever in Papua New Guinea. A series of 14 patients with typhoid fever and ataxia was compared with non-ataxic typhoid patients. Hyponatraemia and hypoalbuminaemia were common in both groups and more severe in the ataxic group. Hypotension was also more common in the ataxic group. These features may reflect more severe disease. All isolates of Salmonella typhi, from both ataxic and non-ataxic patients, were phage type D2 which is endemic around Port Moresby. Tests for autoantibodies cross-reacting with cerebellar tissue were negative. It is possible that cerebellar dysfunction in typhoid fever is more common in association with phage type D2.

Adolescent↗

Electrophysiological findings in patients envenomed following the bite of a Papuan taipan (Oxyuranus scutellatus canni).

Electrophysiological studies were done on patients with systemic neurotoxicity following the bite of a Papuan taipan (Oxyuranus scutellatus canni). Evoked compound muscle action potentials decreased and increased in tandem with clinical deterioration and recovery. Nerve conduction velocities did not change in envenomed patients and were consistent with control studies. Repetitive nerve stimulation studies showed decremental responses in envenomed patients with post-tetanic potentiation followed by post-tetanic exhaustion. The findings are consistent with studies in vitro which suggested that the major action of neurotoxins in Australian taipan venom is at the synapse. The observation that electrophysiological data correlate closely with the clinical condition of the patient has potential application in the assessment of interventions in the management of snake bite victims.

Action Potentials↗

Failure of 3,4-diaminopyridine and edrophonium to produce significant clinical benefit in neurotoxicity following the bite of Papuan taipan (Oxyuranus scutellatus canni).

Progressive systemic neurotoxicity is a common feature in patients envenomed following the bite of a Papuan taipan (Oxyuranus scutellatus canni). Respiratory paralysis, which commonly results, accounts for considerable morbidity and mortality. Established neurotoxicity does not respond to antivenom. In this study, a combination of clinical and electrophysiological variables was used to assess the effect of edrophonium and 3,4-diaminopyridine in patients with significant neurotoxicity. Both drugs produced minor electrophysiological and clinical changes in envenomed patients. This effect was maximal when the 2 drugs were used in combination, but was insufficient to be of significant clinical benefit. Neither drug can be recommended for use in the management of Papuan taipan bite.

4-Aminopyridine↗

The epidemiology of snake bite in Central Province and National Capital District, Papua New Guinea.

Snake bite is an important medical problem in some areas of Papua New Guinea and appears to be most common in the Central Province and National Capital District. The overall incidence for Central Province is 215.5 per 100,000 population, but Kairuku subprovince has an incidence of 526 per 100,000, which is amongst the highest in the world. The clinical pattern of envenoming also varies within the Province, suggesting that different species of snake may be responsible for bites in different areas. Most envenomed patients are bitten during daylight on the lower limb and are rarely able to describe the snake. The mortality rate in Central Province is 7.9 per 100,000; most patients die from ventilatory failure due to severe neurotoxicity. Mortality might be reduced by increased use of compression bandaging as a first aid measure, earlier treatment with antivenom and earlier referral to hospital.

Adolescent↗

The efficacy of antivenom in the treatment of bites by the Papuan taipan (Oxyuranus scutellatus canni).

A prospective series of 156 patients systemically envenomed following the bite of a Papuan taipan (Oxyuranus scutellatus canni) were studied. All patients were treated with appropriate antivenom and clinical course and outcome were compared. The proportion of patients requiring intubation was significantly smaller, and the time to resolution of neurotoxicity and discharge from hospital significantly shorter, in patients receiving antivenom no more than 4 h after the bite. No significant difference in outcome was demonstrated between patients receiving antivenom at various times after 4 h. No difference was demonstrated in the times to restoration of coagulability between the 2 groups. The only significant difference between a small number of patients given 2 vials of antivenom and patients given a single vial at the same time after envenoming was a marginally shorter duration of intubation in those who required it. The study suggests that, to achieve significant clinical benefit in Papuan taipan bite, antivenom must be given as early as possible.

Animals↗

Meningitis caused by Cryptococcus neoformans var. gattii and var. neoformans in Papua New Guinea.

Eleven cases of cryptococcal meningitis were diagnosed and biotyped from September 1991 to August 1992 in Papua New Guinea (PNG). Seven isolates were Cryptococcus neoformans var. gattii from paediatric and adult patients, one with diabetes mellitus and 4 were C. neoformans var. neoformans from adults, of whom 2 had human immunodeficiency virus type 1 (HIV-1) infection, and one each had tuberculosis and Plasmodium vivax malaria. Significant clinical findings were headache, fever, meningism, vomiting, photophobia, papilloedema and cranial nerve lesions. Five patients (45.5%) died; 3 of these were adults with var. gattii and 2 were men with both var. neoformans and HIV-1 infections. This prospective tropical study documents the emergence of C. neoformans var. neoformans in patients with HIV-1 infection in a country where previously var. gattii had predominated in the immunocompetent. There has been no earlier report of cryptococcosis in an HIV-1 seropositive patient in PNG. Despite presumed exposure to both varieties of C. neoformans, var. gattii infections had been most frequent. As HIV-1 spreads, the proportion of hosts infected with var. neoformans may rise. The course of meningitis caused by the 2 varieties of C. neoformans may differ, with mortality in the tropics remaining particularly high. In PNG the environmental source of C. neoformans remains elusive.

Adolescent↗

Visual loss in immunocompetent patients with Cryptococcus neoformans var. gattii meningitis.

In Papua New Guinea cryptococcal meningitis occurs predominantly in immunocompetent patients in whom Cryptococcus neoformans var, gattii is implicated in 95% of cases. Ocular complications are common. We have reviewed ophthalmic findings in 82 immunocompetent patients and have attempted to identify those features of the disease that predict an unfavourable visual outcome. Visual loss occurred in 52.6% of survivors and was associated with optic atrophy following optic disc swelling in 60.9%. Progression of disc swelling to optic atrophy was predicted by the presence of an abducens palsy (P = 0.049) and cerebrospinal fluid (CSF) cryptococcal antigen titres > 1:1024 (P = 0.036). Raised intracranial pressure (defined as opening CSF pressure > or = 300 mm on admission) was not associated with visual loss. Vision deteriorated in 17.3% of patients despite anticryptococcal therapy and in 3.7% it followed curative therapy. The high rate of visual loss in immunocompetent patients with C. neoformans var. gattii infection contrasts with others' experience of immunosuppressed patients with C. neoformans var. neoformans infection, in whom visual loss was rare. This difference may reflect immune mediated optic nerve dysfunction in C. neoformans var. gattii meningitis caused by either compression due to arachnoid adhesions or oedema and inflammatory cell-mediated damage.

Adolescent↗

The effect of corticosteroids on visual loss in Cryptococcus neoformans var. gattii meningitis.

In Papua New Guinea visual loss is a frequent sequal to Cryptococcus neoformans var. gattii meningitis in immunocompetent patients. We have previously postulated that visual loss may occur as a result of the immunological response to infection around the optic nerve. This retrospective study set out to explore the effect of corticosteroids on visual outcome. Sixteen patients received varying doses of corticosteroid (mainly 100-250 mg of hydrocortisone daily for the prevention of febrile reactions to amphotericin) and 10 received anticryptococcal therapy alone. Visual deterioration occurred less frequently in those treated with corticosteroids (2/16 [12.5%] vs. 7/10 [70%], P = 0.007), blindness was less frequent (1/16 [5.3%] vs. 5/10 [50%], P = 0.018), and in 3 patients vision improved. Corticosteroids may have a role in preventing or halting visual loss in C. neoformans var. gattii meningitis in immunocompetent patients.

Adolescent↗

Electrocardiographic abnormalities in patients bitten by taipans (Oxyuranus scutellatus canni) and other elapid snakes in Papua New Guinea.

Envenoming by a number of species of snake may affect the myocardium or cause electrocardiographic changes; several different mechanisms have been proposed. In a prospective study of snake bite in Papua New Guinea, electrocardiographic changes were observed in 36 of 69 patients (52%) envenomed by the taipan (Oxyuranus scutellatus), 2 of 6 (33%) envenomed by death adders (Acanthophis sp.) and one envenomed by the brown snake (Pseudonaja textilis). Septal T wave inversion and bradycardias, including atrioventricular block, were the commonest abnormalities. There was no haemodynamic deterioration. The cause of these changes is uncertain; only 2 of 24 patients (8.3%) with electrocardiographic changes had markedly elevated plasma concentrations of cardiac troponin T, a sensitive and specific marker of myocardial damage. This suggests that myocardial damage is uncommon following bites by these species. Electrocardiographic abnormalities are most likely to have been caused by a direct toxic effect of a venom component upon cardiac myocyte function; in taipan bites, taicatoxin, a calcium channel blocker, might be responsible.

Animals↗

Cryptococcus neoformans in Papua New Guinea: a common pathogen but an elusive source.

Around Port Moresby, Papua New Guinea (PNG), the annual incidence of cryptococcal meningitis is estimated to be up to 42.8 per million population; Cryptococcus neoformans var. gattii is the predominant causative agent. In Australia and California, environmental isolations have established an ecological association of C. neoformans var. gattii with Eucalyptus camaldulensis, E. tereticornis, and more recently E. rudis and E. gomphcephala. In PNG few E. camaldulensis survive experimental planting, E. tereticornis is endemic and there are no records of planting of the non-endemic E. rudis and E. gomphcephela. Despite extensive sampling of eucalypt-associated and other sources, we were unable to identify the ecological niche of C. neoformans var. gattii and neoformans in this region.

Cryptococcus neoformans↗

Community-acquired acinetobacter pneumonia in adults in Papua New Guinea.

Acinetobacter calcoaceticus, an aerobic gram-negative coccobacillus, is a rare cause of community-acquired pneumonia. It most commonly causes nosocomial infections, particularly in elderly debilitated patients who have undergone surgery, instrumentation, and antibiotic therapy. In a study of acute pneumonia in adults, five cases of community-acquired acinetobacter pneumonia were observed over an 11-month period. Other than chronic pulmonary disease (two patients), no serious underlying diseases existed in these patients. Lobar consolidation was the predominant radiologic pattern. The mortality rate was 40%, and mortality was directly related to therapy with inappropriate antibiotics. The reason for this relatively high prevalence of community-acquired acinetobacter pneumonia in the population studied is not known. Possible explanations include the high prevalence of chronic pulmonary disease, indiscriminate use of penicillin, and an unknown immunodeficiency state.

Acinetobacter Infections↗

Tuberculosis of the larynx masquerading as carcinoma.

A patient with laryngeal and pulmonary tuberculosis is described. The similarity between the clinical presentation and gross appearance of laryngeal carcinoma and tuberculosis in this patient and others reported in the literature is emphasized. Laryngeal biopsy is necessary to establish the correct diagnosis, but this must be done only after the proper precautions are taken to reduce the risk of infection to the physician performing the biopsy. Examination of the chest x-ray and acid-fast stain of the sputum are rapid and highly reliable screening tests for laryngeal tuberculosis.

Biopsy↗

Paranoid psychosis related to mefloquine antimalarial prophylaxis.

Mefloquine is an important antimalarial drug for treatment and prophylaxis of chloroquine-resistant malaria. Its use has been associated with neuropsychiatric side-effects. We report a case of paranoid psychosis associated with mefloquine occurring in a remote part of Papua New Guinea. Adverse reactions and contraindications are discussed. This case underlines the importance of awareness of neuropsychiatric side-effects with mefloquine use and of taking a careful psychiatric history before prescribing mefloquine.

Adult↗