Case Report: Seaweed Bezoar Masquerading as a Malignant Obstruction.

Bezoars represent a rare cause of small bowel obstruction (SBO). Nonoperative management of bezoars includes use of endoscopy with mechanical or chemical dissolution methods. When obstruction persists, surgical intervention becomes necessary. Here, we present the case of an Asian woman with a SBO secondary to a phytobezoar masquerading as a malignancy. She presented with two days of acute-on-chronic abdominal pain that started after eating seaweed. Initial computed tomography (CT) scan showed a SBO with a jejunal transition point and ill-defined liver lesions, worrisome for a malignant obstruction with liver metastases. Further imaging, however, showed the resolution of these artifacts. Subsequent laparotomy revealed a small bowel loop with copious obstructing seaweed. A distal stricture was palpated, and the involved segment was resected. Intraoperative liver ultrasound was negative, and final pathology revealed benign small intestine with a mild stricture. Given the rarity of bezoar-related obstructions, the diagnosis is often delayed particularly when confounding factors exist such as our patient's concomitant hepatic findings. Contrast-enhanced CT has a high sensitivity but a lower specificity in identifying bezoars. A high index of suspicion is therefore necessary especially when managing higher risk patients.

Vitreous levels of placental growth factor correlate with activity of proliferative diabetic retinopathy and are not influenced by bevacizumab treatment.

PurposePlacental growth factor (PlGF) is a member of the VEGF family that plays an important role in experimental models of diabetic retinopathy and retinal neovascularization. We aimed to investigate whether vitreous levels of PlGF correlated with proliferative diabetic retinopathy (PDR) status, VEGF levels, and bevacizumab treatment. We also analysed PDR membranes to confirm the presence of the PlGF receptor, FLT1, in endothelial cells.MethodsThis was a case-control study: undiluted vitreous fluid samples were obtained from 28 active PDR patients without preoperative bevacizumab treatment, 21 active PDR patients with preoperative bevacizumab treatment, 18 inactive PDR patients, and 21 control patients. PlGF and VEGF levels in samples were determined by enzyme-linked immunosorbent assay. Immunohistochemistry for FLT1 was performed on human PDR membranes.ResultsCompared to control, vitreous PlGF levels were higher in both active PDR without bevacizumab (P<0.0001) and with bevacizumab (P<0.0001). There was no significant difference in PlGF between active PDR patients without and with bevacizumab (P=0.56). Compared to active PDR, PlGF levels were significantly reduced in inactive PDR (P=0.004). PlGF levels were highly correlated with VEGF levels in active PDR. VEGFR1 was expressed in endothelial cells in human PDR membranes.ConclusionThe strong correlation of PlGF levels with PDR disease status and expression of FLT1 in human PDR membranes suggest that PlGF has a pathogenic role in proliferative diabetic retinopathy. Therapeutic targeting of PlGF with agents like aflibercept may be beneficial.

Adult-onset Kaposiform hemangioendothelioma of the tongue: case report and review of the literature.

We present here a very rare clinical case of a 38-year-old man with Kaposiform hemangioendothelioma (khe) of the tongue who presented to our institution with a growth under the left side of the tongue with no pain or discomfort. There were no enlarged lymph nodes and no significant neurologic findings. Diagnostic histopathology confirmed the lesion to be khe. The tumour was removed surgically, and the surgical specimen confirmed the diagnosis. Follow-up at 3 months shows no clinical evidence of recurrence.

Superficial extraconal blockade for vitreoretinal surgery.

CONTEXT: Needle length plays an important role for the success of ophthalmic block. The standard practice is to use 25 mm needles length; however, unnecessarily long needles may increase the risk of complications especially in the presence of staphyloma or previous scleral buckle. AIMS: This work was designed to compare the efficacy of using 15 and 25 mm needle in performing extraconal block for patients undergoing vitreoretinal surgery. SETTINGS AND DESIGN: Prospective randomized double blinded study. MATERIALS AND METHODS: A total of 120 patients were enrolled in this study and were divided in two groups. In group (1) extraconal block was performed using 25 mm needle, while in group (2) 15 mm needle was used. After primary injection, assessment of the block was done by an anesthesiologist who was unaware of the needle used. If satisfactory akinesia was not achieved a supplementation was provided. At the end of the procedures, patients and surgeons were asked to assess their pain and satisfaction with the anesthetic technique. STATISTICAL ANALYSIS USED: The sample size calculation using N-Quary version 4. Numerical and categorical data were analyzed using an independent sample, a two-tailed t-test, and chi-square test, respectively. RESULTS: The volume of primary injectable was significantly higher in group 2. The two groups were comparable as regards total volume of local anesthetic, supplementation rate, akinesia, pain score, and surgeon satisfaction. CONCLUSIONS: Using 15 mm needle length to perform extraconal blockade for posterior segment procedures is equally effective to 25 mm needle.

Molecular diversity of the repolarizing voltage-gated K+ currents in mouse atrial cells.

Voltage-clamp studies on atrial myocytes isolated from adult and postnatal day 15 (P15) C57BL6 mice demonstrate the presence of three kinetically distinct Ca2+-independent, depolarization-activated outward K+ currents: a fast, transient outward current (Ito,f), a rapidly activating, slowly inactivating current (IK,s) and a non-inactivating, steady-state current (Iss). The time- and voltage-dependent properties of to,f, IK,s and Iss in adult and P15 atrial cells are indistinguishable. Pharmacological experiments reveal the presence of two components of IK,s: one that is blocked selectively by 50 microM 4-aminopyridine (4-AP), and a 4-AP-insensitive component that is blocked by 25 mM TEA; Iss is also partially attenuated by 25 mM TEA. There are also two components of IK,s recovery from steady-state inactivation. To explore the molecular correlates of mouse atrial IK,s and Iss, whole-cell voltage-clamp recordings were obtained from P15 and adult atrial cells isolated from transgenic mice expressing a mutant Kv2.1 alpha subunit (Kv2.1N216Flag) that functions as a dominant negative, and from P15 atrial myocytes exposed to (1 microM) antisense oligodeoxynucleotides (AsODNs) targeted against Kv1.5 or Kv2.1. Peak outward K+ current densities are attenuated significantly in atrial myocytes isolated from P15 and adult Kv2.1N216Flag-expressing animals and in P15 cells exposed to AsODNs targeted against either Kv1.5 or Kv2.1. Analysis of the decay phases of the outward currents evoked during long (5 s) depolarizing voltage steps revealed that IK, s is selectively attenuated in cells exposed to the Kv1.5 AsODN, whereas both IK,s and Iss are attenuated in the presence of the Kv2. 1 AsODN. In P15 and adult Kv2.1N216Flag-expressing atrial cells, mean +/- s.e.m. IK,s and Iss densities are also significantly lower than in non-transgenic atrial cells. In addition, pharmacological experiments reveal that the TEA-sensitive component IK,s is selectively eliminated in P15 and adult Kv2.1N216Flag-expressing atrial cells. Taken together, the results presented here reveal that both Kv1.5 and Kv2.1 contribute to mouse atrial IK,s, consistent with the presence of two molecularly distinct components of IK,s. In addition, Kv2.1 contributes to mouse atrial Iss.

Voltage-gated Na+ channel activity and connexin expression in Cx43-deficient cardiac myocytes.

INTRODUCTION: Dynamic interplay between active and passive electrical properties of cardiac myocytes is based on interrelationships between various channels responsible for depolarizing and repolarizing ionic currents and intercellular conductances. Mice with targeted disruption of the connexin43 (Cx43) gene have hearts completely devoid of Cx43, the principal gap junctional protein expressed in mammalian hearts. METHODS AND RESULTS: To determine whether cardiac myocytes that develop in an abnormal environment of reduced intercellular coupling have altered active membrane properties, we studied whole cell action potentials, Na+ channel currents, and Na+ channel expression and distribution via immunoblotting and confocal immunofluorescence in neonatal ventricular myocytes isolated from Cx43 wild-type, heterozygous, and homozygous null hearts. Action potential morphology, peak Na+ current, activation and inactivation kinetics, and Na+ channel protein expression and distribution were not different among myocytes isolated from wild-type, heterozygous, or null hearts. Active membrane properties and Na+ channel activity were completely normal in Cx43-deficient myocytes isolated from hearts that have been shown to exhibit markedly reduced Cx43 expression, gap junction number, and epicardial conduction delay. CONCLUSION: Despite a genetic inability to produce Cx43 and a developmental history that culminates in marked gross cardiac morphologic abnormalities, premature death, and myocardial inexcitability ex vivo, cardiac Na+ channel distribution and function appear to be normal in Cx43 null hearts. Although intimate structural and functional interrelationships have been described between ion channels and gap junction channels, expression and function of Na+ channels is not affected by the absence of Cx43.

Molecular correlates of the calcium-independent, depolarization-activated K+ currents in rat atrial myocytes.

1. In adult rat atrial myocytes, three kinetically distinct Ca2+-independent depolarization-activated outward K+ currents, IK, fast, IK,slow and Iss, have been separated and characterized. 2. To test directly the hypothesis that different voltage-dependent K+ channel (Kv channel) alpha subunits underlie rat atrial IK,fast, IK, slow and Iss, the effects of antisense oligodeoxynucleotides (AsODNs) targeted against the translation start sites of the Kv alpha subunits Kv1.2, Kv1.5, Kv4.2, Kv4.3, Kv2.1 and KvLQT1 were examined. 3. Control experiments on heterologously expressed Kv alpha subunits revealed that each AsODN is selective for the subunit against which it was targeted. 4. Peak outward K+ currents were attenuated significantly in rat atrial myocytes exposed to AsODNs targeted against Kv4.2, Kv1.2 and Kv1.5, whereas AsODNs targeted against Kv2.1, Kv4.3 and KvLQT1 were without effects. 5. No measurable effects on inwardly rectifying K+ currents (IK1) were observed in atrial cells exposed to any of the Kv alpha subunit AsODNs. 6. Kinetic analysis of the currents evoked during long (10 s) depolarizing voltage steps revealed that AsODNs targeted against Kv4.2, Kv1.2 and Kv1.5 selectively attenuate rat atrial IK,fast, IK, slow and Iss, respectively, thus demonstrating that the molecular correlates of rat atrial IK,fast, IK,slow and Iss are distinct. 7. The lack of effect of the Kv4.3 AsODNs on peak outward K+ currents reveals that Kv4.2 and Kv4.3 do not heteromultimerize in rat atria in vivo. In addition, the finding that Kv1.2 and Kv1.5 contribute to distinct K+ currents in rat atrial myocytes demonstrates that Kv1.2 and Kv1.5 also do not associate in rat atria in vivo.

A novel locus for Leber congenital amaurosis on chromosome 14q24.

Leber congenital amaurosis (LCA) is a clinically and genetically heterogeneous autosomal recessive retinal dystrophy and the most common genetic cause of congenital visual impairment. We used a DNA pooling strategy comparing the genotypes of affected to unaffected control pools in a genome-wide search for identity-by-descent on a consanguineous Saudi Arabian LCA family. A shift to homozygosity was observed in the affected DNA pool compared with the control pool at linked markers D14S606 and D14S610. Genotyping of individual DNA samples from the entire pedigree for marker D14S74, closely linked to these loci, and several flanking markers confirmed linkage with a ZMAX=13.29 at theta=0.0. These data assign a third locus (LCA3) for LCA to chromosome 14q24. This locus and the previously identified loci are excluded for other Saudi Arabian pedigrees, both confirming that this clinical disorder is genetically heterogeneous and that additional LCA genes remain to be identified.

Retinal detachment surgery in Marfan's syndrome.

BACKGROUND: Retinal detachment is a known complication of Marfan's syndrome. The literature is scarce on the results of surgery in these cases. PURPOSE: To determine the functional and anatomic outcome of retinal detachment surgery in Marfan's syndrome. METHOD: Retrospective review of charts of Marfan's syndrome patients who had retinal detachment surgery at King Khaled Eye Specialist Hospital between 1983 and 1995. RESULTS: Fourteen patients with 16 surgically treated eyes were identified. Retinal detachment was bilateral in 9/13 (69%) patients. The lens was ectopic in all eyes. Retinal breaks were small horseshoe tears or holes located anterior to the equator in 11/16 (69%) eyes. The retina of 12/16 (75%) eyes remained successfully reattached after a follow-up ranging from 4 to 132 months. All 12 eyes had visual acuity of 20/300 or better (range, 20/30-20/300). Eight of these eyes had visual acuity of 20/125 or better. The cause of failure in the remaining four eyes was proliferative vitreoretinopathy. CONCLUSIONS: Results of surgical repair of retinal detachment in Marfan's syndrome were better than previously thought. Bilaterality of detachment is extremely high, which justifies considering prophylactic treatment of the fellow eye in these patients.

Molecular mechanisms of the reversal of imipramine-induced sodium channel blockade by alkalinization in human cardiac myocytes.

BACKGROUND: Alkalinizing agents reverse cardiotoxicity of a variety of sodium channel blockers, including tricyclic antidepressants, but their mechanisms of action are poorly understood. PURPOSE: To establish the mechanisms by which alkalinization diminishes the sodium channel blocking action of imipramine. METHODS: The whole-cell voltage-clamp technique was used to measure INa during a variety of depolarizing pulse protocols in isolated human atrial myocytes, in the presence and absence of imipramine. A three-state model was used to analyze state-dependent INa block. RESULTS: Imipramine (1 and 5 microM) strongly inhibited INa. Experimental data and piecewise exponential analysis suggested significant binding to both activated and inactivated states. Alkalosis antagonized imipramine-induced INa blockade by increasing the unbinding rate, with intracellular alkalosis being more effective than extracellular alkalosis. The dissociation constant (Kd) for the inactivated state was increased from 0.55 to 1.40 microM by extracellular alkalosis and to 2.51 microM by intracellular alkalosis. Along with the reversal of drug-induced shifts in the inactivation curve, these data indicate that alkalosis on either side of the membrane antagonized drug interactions with the inactivated state. On the other hand, only intracellular alkalosis antagonized activated state block, increasing the Kd from 0.67 microM to 2.18 microM, while extracellular alkalosis left the activated state Kd unaltered at 0.67 microM. CONCLUSIONS: Alkalinization antagonizes the INa-blocking action of imipramine by promoting unbinding from the receptor. Intracellular alkalosis has a particularly important effect related to the activated-state interaction. The lipid-soluble, uncharged moiety appears to be a critical determinant of imipramine's ability to dissociate from the Na+ channel receptor.

Phacomorphic glaucoma associated with choroidal melanoma.

Patients with phacomorphic glaucoma present with mature cataract, shallowing of the anterior chamber, and angle-closure glaucoma. The opaque ocular media due to cataract formation usually precludes visualization of the posterior segment of the affected eyes. The authors describe a 65-year-old man who presented with reduced vision and clinical findings typical of phacomorphic glaucoma. Preoperative ultrasonography revealed an intraocular tumor, and magnetic resonance imaging showed a high signal intensity in T1-weighted images and a low signal intensity in T2-weighted images consistent with choroidal melanoma. Histopathologic examination of the tumor after enucleation confirmed the diagnosis. The clinical findings characteristic of phacomorphic glaucoma may be associated with choroidal melanoma. Ultrasonography or other imaging studies should be performed on eyes with phacomorphic glaucoma and opaque ocular media to allow timely detection of any mass lesion and to guide appropriate surgical management.

Recalcitrant malignant glaucoma following pars plana vitrectomy, scleral buckle, and extracapsular cataract extraction with posterior chamber intraocular lens implantation.

Pars plana vitrectomy is employed to treat cases of aqueous misdirection that are refractory to medical and laser treatment. The authors describe a 65-year-old man without previous aqueous misdirection in whom this condition developed after a procedure that included pars plana vitrectomy. The aqueous misdirection recurred despite multiple interventions, including medical treatment, transiently successful Nd:YAG laser capsulo-hyaloidotomy, and surgical disruption of the anterior hyaloid face. It finally resolved after repeated pars plana vitrectomy with hyaloido-capsulo-iridectomy. There has been no recurrence 7 months after this procedure. The authors conclude that the surgical treatment of aqueous misdirection refractory to more conservative measures should include adequate disruption of the anterior hyaloid to prevent recurrence.

Endophthalmitis cluster from contaminated donor corneas following penetrating keratoplasty.

OBJECTIVE: To attempt to identify common events or factors in four cases of endophthalmitis that developed after penetrating keratoplasty performed within a 1-week interval. DESIGN: Case series. SETTING: Tertiary care eye hospital in Riyadh, Saudi Arabia. PATIENTS: Four patients in whom endophthalmitis developed after penetrating keratoplasty performed in May 1993. OUTCOME MEASURES: Source of donor tissue, transportation of corneas, handling of corneas at the eye hospital, and causative organism and sensitivity profile. RESULTS: The donor tissue in all four cases originated from the same eye bank. Organisms were cultured from 10 of the 11 donor rims from eye bank A tissue used during the week in question. The causative organisms were Enterococcus faecalis in three patients and Torulopsis glabrata in one patient. In each case the same organism was cultured from the recipient eye and the corresponding donor rim. Two of the four patients had a favourable outcome. CONCLUSIONS: Donor rim culture is essential if the cause of endophthalmitis after penetrating keratoplasty is to be determined. Close communication between eye bank personnel, the microbiology laboratory and the operating surgeon is important as it may influence early detection, choice of treatment and outcome of endophthalmitis after penetrating keratoplasty. Epidemiologic studies from both the source eye bank and the recipient facility are required to fully investigate the cause of a cluster of endophthalmitis cases from contaminated donor tissue following penetrating keratoplasty.

Tachycardia-induced changes in Na+ current in a chronic dog model of atrial fibrillation.

We have previously shown that chronic rapid atrial activation (400 bpm) reduces atrial conduction velocity in dogs, contributing to the development of a substrate supporting sustained atrial fibrillation (AF). However, the cellular and ionic mechanisms underlying these functional changes have not been defined. We applied whole-cell patch-clamp techniques to atrial myocytes from dogs subjected to atrial pacing at 400 bpm for 7 days (P7, n = 6) and 42 days (P42, n = 5) and compared the results with those from sham-operated dogs similarly instrumented but without pacemaker activation (P0, n = 6). Rapid atrial pacing allowed for the induction of sustained AF in 67% and 100% of dogs paced for 7 and 42 days, respectively, and significantly decreased conduction velocity under P7 and P42 conditions. In dogs paced for 7 days, Na+ current (INa) density was reduced by 28% at -40 mV (P < .0001, n = 59 cells). INa changes were even more decreased under P42 conditions, by approximately 52% at -40 mV (P < .0001): from -78.7 +/- 4.6 pA/pF (P0, n = 28 cells) to -37.7 +/- 3.0 pA/pF (P42, n = 43 cells). INa was significantly reduced at all voltages ranging from -65 to -10 mV. Voltage-dependent activation and inactivation properties, activation kinetics, and recovery from inactivation were not altered by rapid atrial pacing; however, inactivation kinetics were slowed. AF duration was related to mean INa in each dog (r2 = .573, P < .001). We conclude that rapid atrial activation significantly reduces both conduction velocity and INa density. Since INa is a major determinant of conduction velocity, our data point to INa reduction as a potentially important mechanism contributing to the substrate for AF in this model.

Radiation therapy for retinoblastoma: a retrospective review of 120 patients.

PURPOSE: To characterize the patient population and treatment outcomes in patients with Retinoblastoma (RB) referred for External Beam Orbital Radiotherapy (EBORT) to King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, Saudi Arabia from 1976 to 1993. METHODS AND MATERIALS: A retrospective study of 120 patients with RB affecting a total of 192 eyes. Patients were divided into three groups. Group A are 60 patients (64 eyes) treated with EBORT to the intact eye to preserve vision. Reese-Ellsworth (RE) Staging was: 1: 12%; 2: 10%; 3: 12%; 4: 23%; and 5: 43%. Twenty-eight patients (47%) also received Vincristine, Adriamycin, and Cyclophosphamide chemotherapy (C/T). Mean follow-up, per patient, was 48.5 months. Standard treatment until 1992 was 45 Gy in 12 fractions of 3.75 Gy, three times weekly over 18 days. Assuming the alpha/beta ratio for early effects and tumor control at 10, Tk = 21 days, Tpot = 5 days, then the Biological Equivalent Dose (BED) was 62 Gy10 for early effects, and 101 Gy3 for late effects. Group B are 28 patients (28 eyes) treated for curative intent with EBORT to the orbit for locally advanced disease, usually after enucleation (24 eyes). Nineteen patients (83%) also had C/T. Mean follow-up was 22.6 months. Group C are 37 patients with advanced disease treated with radiotherapy for palliation. Seventeen (46%) also received C/T. Mean follow-up was 11.7 months. RESULTS: Group A-following EBORT useful vision was retained in RE Stage 1 to 5: 7 of 7, 6 of 6, 4 of 8, 10 of 15, and 7 of 28 eyes, respectively. There was no significant difference between patients who received adjuvant chemotherapy and those who did not. Complications included cataract (27%), retinopathy (25%), vitreous hemorrhage (19%), and orbital deformities (11%). In Group B the local control rate was 71%. In Group C, 10 (27%) of the 37 patients were alive at last contact, and 27 (73%) were either terminal or dead of disease. None of Group A or B patients had positive CSF cytology, bone scan, or bone marrow examination. In Group C 19% had positive CSF cytology, and bone marrow, and 14% had a positive bone scan. CONCLUSIONS: 1) EBORT preserved useful vision in a significant proportion of patients even in eyes with advanced RE Stage RB, but longer follow-up is likely to reveal an even higher complication rate with this regime. 2) High dose per fraction probably contributed to the increased complications. 3) Chemotherapy did not demonstrate any effect on retaining vision in this study. 4) For disease that is confined to within the eye clinically and radiologically, invasive procedures for CSF cytology, bone marrow examination, and bone scan do not seem warranted. 5) The optimum technique, fractionation, and dosage for RB is still not well defined.

Workup for metastatic retinoblastoma. A review of 261 patients.

PURPOSE: The means available to screen for retinoblastoma metastases, including bone marrow aspiration, lumbar puncture, and radionuclide scans, offer variable usefulness at different stages of the disease. In this study, the authors attempted to assess the value of these tests as part of the initial workup for metastases. METHODS: Medical files of 261 patients with retinoblastoma were reviewed, and the results of bone marrow, lumbar puncture, and bone and liver radionuclide scans were correlated with the laterality, clinical staging, and histopathologic findings. The presence or absence of tumor in the choroid and the optic nerve also were correlated with the results of diagnostic tests. RESULTS: Of 261 patients with retinoblastoma, 147 (56.3%) and 114 (43.7%) had unilateral and bilateral disease, respectively; 11.6% of unilateral cases and 14.9% of bilateral cases had distant metastasis (P = 0.2). Bone marrow aspirations were performed on 101 patients (38.7%), and 10 (9.9%), of these specimens showed the presence of retinoblastoma cells in the aspirate. Ninety-four (36%) of the patients were examined with spinal tap cytology, and the results of four (4.3%) of these were positive for tumor cells. Radionuclide bone and liver scans were performed on 49 (18.8%) and 48 (18.4%) patients, respectively; 5 (10.2%) had abnormal bone scans and 3 (6.2%) had abnormal liver scans. The average age in the metastatic group was 3.1 years, whereas the average age in the nonmetastatic group was 2.3 years. All of our abnormal test results were found in patients with stages III and IV disease, with the exception of one abnormal lumbar puncture in a patient with stage II disease. The correlation of diagnostic tests with the histopathologic findings showed that with no choroidal involvement, no positive diagnostic tests were encountered. Correlation between positive diagnostic test results and the level of optic nerve involvement failed to indicate any trends. CONCLUSION: Our study indicated a good interrelation between the positivity of diagnostic tests (bone marrow and bone scan) and higher stages of the disease (stages III and IV) and choroidal involvement in enucleated eyes, with statistically significant correlations; correlations with lumbar puncture and liver scan were not significant.

Retinal detachment associated with type III retinoblastoma regression after cryotherapy and external-beam radiotherapy.

PURPOSE: To report a child with rhegmatogenous retinal detachment originating from a focus of type III retinoblastoma regression after cryotherapy and external-beam radiation therapy. METHOD: Retinal detachment and multiple retinal holes, which were closely associated with the calcified mass of the regressed retinoblastoma, were treated with cryotherapy and scleral buckle. RESULTS: Positioning the regressed tumor and the retinal holes on the scleral buckle closed the holes. Subretinal fluid gradually reabsorbed after surgery, and complete retinal reattachment resulted. CONCLUSION: Rhegmatogenous retinal detachment is rare in patients with retinoblastoma, and scleral buckle can successfully manage such cases. In our patient, the detachment probably resulted from retinal necrosis secondary to cryotherapy and external-beam radiation therapy.

Treatment of severe respiratory failure during status asthmaticus in children and adolescents using high flow oxygen and sodium bicarbonate.

OBJECTIVE: Status asthmaticus with respiratory failure is a potentially fatal complication of bronchial asthma. To prevent a fatality in status asthmaticus with respiratory failure, treatment with intravenous isoproterenol or mechanical ventilation has been advocated. These interventions also have serious potential complications, however, and while continuous inhalation of beta agonists has shown promise, the optimal therapy of severe status asthmaticus remains unclear. This paper describes our experience with a treatment protocol used in status asthmaticus with respiratory failure that seeks to avoid intravenous isoproterenol or assisted ventilation. STUDY DESIGN: Case series of pediatric intensive care patients with severe respiratory failure due to status asthmaticus. Six children and adolescents experienced a total of nine episodes of severe respiratory failure due to status asthmaticus. RESULTS: In seven of the nine episodes the patients were managed without either intravenous isoproterenol or mechanical ventilation. Hypercarbia persisted for an average of 25 hours (range 17 to 40 hours) in these seven episodes. All subjects recovered without notable sequelae. In two episodes, clinical and blood gas deterioration led to mechanical ventilation. Ventilation was required for 112 and 42 hours, respectively, in these episodes and the patients developed either pneumothorax or pneumomediastinum during ventilation. CONCLUSION: Using a protocol initiated in 1978 for correction of hypoxia and acidemia, many patients with severe respiratory failure from status asthmaticus can be treated without isoproterenol or mechanical ventilation. Since those treatments have significant risks, consideration should be given to this intervention before resorting to them.

Presentation of retinoblastoma as phthisis bulbi.

PURPOSE: We sought to determine the incidence of retinoblastoma patients who presented with phthisis bulbi. METHODS: The medical records of 272 patients in the King Khaled Eye Specialist Hospital Retinoblastoma Registry were retrospectively studied. Clinical records, radiological investigations and histopathological slides were reviewed. RESULTS: We found that 2.7% of patients had retinoblastoma coincident with phthisis bulbi. Five of 10 patients had bilateral retinoblastoma; in the others it was unilateral. Radiologically, intraocular calcification was present in all except one case. All enucleated phthisical globes had residual viable tumour cells; optic nerve extension was found in 2 patients who had long-standing phthisis bulbi. CONCLUSION: Phthisis bulbi is an uncommon presenting sign of retinoblastoma which often occurs after an ocular inflammatory episode possibly related to intraocular tumour infarction. In most cases the tumour is not visible because of intraocular disruption. That every enucleated eye in this series harboured well-differentiated tumour cells underlies the seriousness with which phthisis bulbi of unknown origin in children should be investigated for retinoblastoma.