New concepts in the diagnosis and management of optic nerve sheath meningioma.

Optic nerve sheath meningiomas are by far the most common tumors of the optic nerve sheath. The diagnosis can be suspected in most cases from clinical findings and supported by the results of neuroimaging, obviating tissue biopsy in the majority of cases. Observation may be appropriate in patients with mild or no visual deficit or in whom visual loss is not progressing, whereas stereotactic fractionated radiation therapy has been demonstrated to improve or stabilize vision in progressive or advanced cases. Attempts at surgical excision, and even biopsy, of optic nerve sheath meningiomas are associated with a high risk of blindness and should be reserved for the rare case of an anteriorly located, primarily exophytic tumor with focal involvement of the dural sheath.     

Detection of Mycoplasma and its antibodies in the blood of HIV-positive patients and in healthy persons]

The comparative study of HIV-positive and clinically healthy persons has indicated that the antigens of M. pneumoniae, M. fermentans and U. urealyticum are encountered nearly twice more frequently in the blood of HIV-infected patients than in that of healthy individuals. Mycoplasma antibodies are detected in HIV-positive persons 12 times more frequently than in healthy ones. Among the HIV-infected persons there are those who have simultaneously antigens of some Mycoplasma species.     

The hidden mortality in surgically treated necrotizing enterocolitis: fungal sepsis

From 1979 to 1986, 82 infants underwent surgical treatment for necrotizing enterocolitis (NEC), with 36 deaths. The records of 30 of the 36 infants who died were available for review. Fungal colonization and sepsis, the sites of infection, and timing of diagnosis and therapy were determined. Sixteen of 30 (53%) neonates had no evidence of fungus. Six (20%) were colonized with Candida species. Eight (27%) had fungal sepsis, with two of these eight found only at necropsy. Positive fungal blood cultures were a late finding. In only four of the six patients with positive blood cultures were the results known in time to initiate treatment with amphotericin B. Two of these four babies received less than 2 days of amphotericin B treatment prior to death. Fungal sepsis is a significant lethal factor in the surgical mortality of NEC. Vigorous efforts at earlier diagnosis are mandatory.     

Bilateral ischemic optic neuropathy and retinal vascular occlusions associated with lymphoma and sepsis. Clinicopathologic correlation

The authors report the clinicopathologic correlation of a patient with non-Hodgkin's mixed-cell lymphoma who had impairment of the circulation of the optic nerve and retina in both eyes. The results of histopathologic examination showed that the pial septa of the optic nerves were infiltrated by lymphoma and that there was extensive infarction of the orbital portions of both optic nerves and occlusion of both central retinal arteries and the right central retinal vein by thrombi with bacteria. The infiltration of the optic nerves seemed to be resistant to therapy.     

Cerebral blood flow changes in normal aging: Spect measurements

Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both ¹³³Xenon (¹³³Xe) (47 subjects, 47–82 years old) and ⁹⁹Tc-hexamethylpropyleneamine oxime (⁹⁹Tc-HMPAO) (27 subjects, 47–80 years old). The ¹³³Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The ⁹⁹Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study.     

Role of oxidants in microbial pathophysiology.

Reactive oxidant species (superoxide, hydrogen peroxide, hydroxyl radical, hypohalous acid, and nitric oxide) are involved in many of the complex interactions between the invading microorganism and its host. Regardless of the source of these compounds or whether they are produced under normal conditions or those of oxidative stress, these oxidants exhibit a broad range of toxic effects to biomolecules that are essential for cell survival. Production of these oxidants by microorganisms enables them to have a survival advantage in their environment. Host oxidant production, especially by phagocytes, is a counteractive mechanism aimed at microbial killing. However, this mechanism may be contribute to a deleterious consequence of oxidant exposure, i.e., inflammatory tissue injury. Both the host and the microorganism have evolved complex adaptive mechanisms to deflect oxidant-mediated damage, including enzymatic and nonenzymatic oxidant-scavenging systems. This review discusses the formation of reactive oxidant species in vivo and how they mediate many of the processes involved in the complex interplay between microbial invasion and host defense.     

Outbreak of measles in a teenage school population: the need to immunize susceptible adolescents.

An outbreak of measles occurred in a community school and the surrounding area in Crowborough, East Sussex, UK, from December 1992 to February 1993. There were 96 suspected cases reported: 66 cases among 1673 students at one school and 30 community cases. The majority of suspected cases were in those aged 11-17 (78%), 2 cases occurred in infants < 1 year old and 8 cases in adults aged 18 years or over. Data collected on 60 (91%) of the 66 suspect school cases showed 56 (93%) had an illness which met a case definition of measles. Eighteen had confirmatory IgM measles antibody. Two cases were hospitalized. The local percentage uptake for measles immunization for the school age years affected varied between 64% and 84%. A survey of parents showed that approximately 74% of the students attending the school had a history of measles immunization. The immunization rates reported by parents for children who developed measles was 21%, (29% based on GP records) compared with 77% for those who remained well. Vaccine efficacy was estimated to be 92%. This outbreak, along with others recently reported in older unimmunized children in the UK, reinforces the need for catch-up immunization programmes to reach this susceptible group of adolescents.     

Hyperfractionated radiation therapy and concurrent 5-fluorouracil, cisplatin and mitomycin-C in head and neck carcinoma. A pilot study.

Seventeen patients were entered into a Phase I/II trial of concurrent hyperfractionated radiation therapy (7,440 cGy total dose; 120 cGy b.i.d.) combined with constant infusion of 5-fluorouracil (5-FU) (1,000 mg/m2/24 hours for 72 hours) and cisplatin (DDP) (50 mg/m2) for a total of three cycles. Thirteen patients had Stage IV disease; three, Stage III disease; and one, Stage II hypopharyngeal disease. Thirteen of 17 patients had positive cervical lymph nodes, and the mean size of the largest lymph node was 5.5 x 5.1 cm. The patients were not treated with planned adjunctive surgery except for one patient who had a radical neck dissection for massive, rapidly growing cervical adenopathy, which recurred promptly within 1 month before the initiation of protocol therapy. After the initial six patients were entered, mitomycin-C (Mito 8 mg/m2) was added during the second cycle. All the patients completed the planned course of radiotherapy with a median dose of 7,440 cGy and a mean dose of 7,248 cGy except for two patients who died--one from toxicity and the other, suicide. The predominant toxicity was mucositis, which was grade 3/4 in 11 of 15 patients, resulting in an average interruption of radiation therapy of 12 days. Weight loss was significant and was on the average 12% of baseline weight. Hematological toxicity was mild in the 5-FU/DDP group (only one grade 3 toxicity of six) and severe in the 5-FU/DDP/Mito-treated patients (five of eight patients having grade 3/4 toxicity including one leukopenic pneumonitis death). Additional toxicity included one parapharyngeal cellulitis, which responded to antibiotics. Noncompliance with the complex regimen was only seen in three patients. One patient refused b.i.d. radiation therapy, and one patient refused further chemotherapy after the first cycle. Additionally, one patient who had a severe ethanol withdrawal reaction during the first cycle of 5-FU/DDP did not receive further chemotherapy. The complete response rate of both primary site and neck by the protocol regimen alone was 71%. However, two patients, one from each group, did undergo salvage neck dissection, and the locoregional control is currently 73%, with a mean follow-up time of 18.4 months. The feasibility of combining hyperfractionated radiation therapy with aggressive concurrent chemotherapy was demonstrated. The response and local control rate justifies the added toxicity of concurrent chemotherapy and radiation therapy.     

Localized cerebral proton MR spectroscopy in HIV infection and AIDS.

PURPOSETo document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.METHODWe studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.RESULTSReduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).CONCLUSIONSBy clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease.