Urea cycle disorders and indications for liver transplantation

Urea cycle disorders (UCD) are inborn errors of metabolism caused by deficiency of enzymes required to convert nitrogen from ammonia into urea. Current paradigms of treatment focus on dietary manipulations, ammonia scavenger drugs, and liver transplantation. The aim of this study was to describe the characteristics and indication of liver transplantation in UCD in a tertiary hospital. We performed a retrospective study of children with UCD seen in the period 2000-2021. Data was collected on clinical onset, hyperammonemia severity, evolution and liver transplantation. There were 33 patients in the study period, whose diagnosis were: ornithine transcarbamylase (OTC, n = 20, 10 females), argininosuccinate synthetase (ASS, n = 6), carbamylphosphate synthetase 1 (CPS1, n = 4), argininosuccinate lyase (ASL, n = 2) and N-acetylglutamate synthetase (NAGS, n = 1) deficiency. Thirty one were detected because of clinical symptoms (45% with neonatal onset). The other 2 were diagnosed being presymptomatic, by neonatal/family screening. Neonatal forms (n = 14) were more severe, all of them presented during the first week of life as severe hyperammonemia (mean peak 1,152 µmol/L). Seven patients died (6 at debut) and all survivors received transplantation. There was no mortality among the late forms. Of the 27 patients who did not die in the neonatal period, 16 (59%) received liver transplantationwith 100% survival, normal protein tolerance and usual need of citrulline supplementation. The transplant's metabolic success was accompanied by neurologic sequelae in 69%, but there was no progression of brain damage. Decision of continuous medical treatment in 11 patients appeared to be related with preserved neurodevelopment and fewer metabolic crises.

[Self-inflicted laser-induced maculopathy in adolescence]

Reports of laser-induced ocular injuries have become more frequent in recent years, especially due to high-energy laser pointers. The article presents for the first time in the German literature a case of self-inflicted laser-induced maculopathy in an adolescent. In addition to the clinical findings, the results of funduscopy and spectral domain optical coherence tomography (SD-OCT) follow-up are presented.

[Frosted branch angiitis : Clinical findings and Spectralis OCT follow-up]

Frosted branch angiitis is a special form of retinal vasculitis, which has only rarely been reported in the literature. Although the majority of cases of frosted branch angiitis are idiopathic, a systematic clinical work-up should be done in order to exclude other causes, such as infectious and autoimmune diseases. The aim of this study was to correlate the clinical findings with the images obtained during follow-up by spectral domain optical coherence tomography (OCT).

[Laser-induced Maculopathy Caused by Strangers]

Background: Laser-induced ocular injuries are of public interest, especially when caused by strangers. Clinical signs and follow-up: Two laser-induced maculopathies were presented which had been caused by strangers. Morphological findings were shown by funduscopy and Spectralis Domain OCT follow-up. Conclusion: Severe retina injuries can be induced by laser pointers of higher classes.

[Sympathetic ophthalmia following repeated pars plana vitrectomy : Clinical findings and spectral domain OCT follow-up]

Sympathetic ophthalmia is a rare form of bilateral granulomatous panuveitis, occurring after penetrating trauma. Hitherto, sympathetic ophthalmia after vitrectomy has only occasionally been described in the literature. This case report presents a female patient with sympathetic ophthalmia after repeated pars plana vitrectomy on the basis of clinical findings and follow-up with fluorescein angiography, spectral domain OCT, and histopathology.

Human case of Onchocerca lupi infection, Germany, August 2014

Onchocerca lupi, a nematode parasite infecting dogs and cats with a hitherto unknown arthropod vector, is also being recognised as a parasite also responsible for human eye infections. Here we describe a case of human eye infection diagnosed molecularly by nematode 12S rDNA PCR in a German patient who had travelled to Tunisia and Turkey. The patient recovered after treatment with antibiotic and anti-inflammatory therapy.

3D vs 2D qualitative and semiquantitative evaluation of the glaucomatous optic disc atrophy using computer-assisted stereophotography

BACKGROUND AND PURPOSE

Real colour documentation of the optic nerve head (ONH) is one of the most important methods to identify the early progression of glaucomatous optic nerve damage. This study compares the qualitative and semiquantitative evaluation of ONH photographs, using a 3D time-multiplexing system and conventional 2D photography, visualised on a computer monitor.

PATIENTS AND METHODS

Stereophotographs of the ONH were converted by special software in a 3D file. The same images were shown in 2D and 3D to 22 subjects with different training grades (residents and ophthalmologists). The evaluation based on a standardised questionnaire, containing semiquantitative parameters of the ONH. A weighted score for quality of ONH assessment counted the correct answers of the observers to compare their evaluation in 2D to the one made in 3D.

RESULTS

All of the observers achieved a significant better evaluation of the ONH with 3D than with 2D images. No significant differences were observed between both groups. Classification errors with respect to the 'gold standard' were lower for 3D measurements as compared with 2D measurements (P=0.007). No significant differences were observed between the gold standard and residents or ophthalmologists for the ONH size, but for the c/dratio the stereoscopic images lead to better results.

CONCLUSION

This study showed a better evaluation of parameters associated with the glaucomatous ONH atrophy with 3D images compared with 2D, independent of the clinical training grade. The computer-based evaluation of the ONH atrophy by using a time-multiplexing system (shutter-glasses) may improve the diagnosis of glaucoma patients.

[Time-multiplexing stereophotography: 2D and 3D qualitative and semiquantitative evaluation of glaucomatous optic disc atrophy]

PURPOSE

Real color documentation of the optic nerve head (ONH) is one of the most important methods in identifying early progression of glaucomatous optic nerve damage. This study qualitatively and semiquantitatively compared the evaluation of ONH photographs, using a 3D time-multiplexing system and conventional 2D photography, visualized on a computer monitor.

PATIENTS AND METHODS

Twelve 15 degrees sequential stereophotographs from the Erlangen Glaucoma Registry were scanned by a SprintScan 35 Plus Film scanner (Polaroid, Waltham, MA, USA) and converted by computer software (3D-PIX, NuVision, McNaughton Inc., Beaverton, OR, USA) in jps format (3D). The same ONH images were shown in 2D and 3D to 22 subjects: 12 residents and ten ophthalmologists and evaluated using a standardized questionnaire.

RESULTS

We observed a significantly better evaluation with stereoscopic pictures for both qualitative parameters (cup depth, visibility of the retinal nerve fibers, and the thinnest location of the neuroretinal rim) and quantitative parameters (c/d ratio and size of the disc, depending on the training level: in 3D better evaluation by the residents, in 2D by the ophthalmologists). With 2D pictures, we found better evaluation of the B zone and the stage of atrophy. Other than the method used for the entire evaluation, there was no significant difference between the groups. For the parameters weighed for clinical importance, the score of correct answers was significantly better with stereoscopic pictures.

CONCLUSION

This study showed a significantly better evaluation of glaucomatous ONH atrophy with 3D images than with 2D pictures, independently of the evaluators' clinical training level. The computer-based evaluation of ONH atrophy using a time-multiplexing system (shutter glasses) may improve the diagnosis of glaucoma patients.

[Orbito-palpebral emphysema due to ethmoidal fracture]

BACKGROUND

Orbito-palpebral emphysema is a frequent pathological entity due to head injury. We report on a patient and correlate the clinical view and computer tomography findings.

CASE REPORT

A 17-year-old male was referred to our hospital after a blunt trauma to his head. Visual acuity was 1,0. Diplopia, restricted motility and exophthalmus about 4 mm were found.

CONCLUSION

If swelling of the lid is found orbito-palpebral emphysema should be thought of to initiate appropriate therapy to avoid possible severe complications, for example, occlusion of the retinal central artery.

[Fulminant acute retinal necrosis 10 months after ipsilateral herpes simplex virus encephalitis - a case report]

BACKGROUND

Cases of acute retinal necrosis caused by herpes simplex virus are rare. We present here a case with a very fast progression 10 months after a primary herpetic encephalitis in an immunocompetent patient.

CASE REPORT

A 36-year-old otherwise healthy man presented in our hospital with an acute painless loss of vision on the left eye. Initial examination of the fundus showed peripheral retinal necrosis with intra- and preretinal haemorrhages and sheathing of retinal venules. Diagnosis was made by detection of viral DNA in vitreous fluid. Although an antiviral therapy with high doses of acyclovir was started, a vitrectomy with silicon oil instillation was necessary to stabilise the necrotic retina.

CONCLUSION

Acute retinal necrosis is relatively rare, and fast diagnosis is required. A detailed case history with attention to previous infections with herpes simplex virus as well as clinical signs were the key for the diagnosis.

Visual evoked potentials under luminance contrast and color contrast stimulation in glaucoma diagnosis

PURPOSE

To evaluate the diagnostic value of visual evoked potential (VEP) assessment with luminance-contrast and color-contrast stimulation in the detection of glaucoma.

PATIENTS AND METHODS

The study included 59 patients (96 eyes) with glaucomatous changes of the optic disc and visual field defects and 58 control eyes of 29 healthy patients. Four types of pattern VEP stimulation (0.9 cycle/degree) were performed in all patients: achromatic, alternating sine-wave stripe pattern: 6 reversals per second, contrast of 10% (activation of predominantly the magnocellular pathway); isoluminant, red-green stripe pattern: 83.3 milliseconds onset, 83.3 milliseconds offset, contrast of 30% and 80% (activation of predominantly the parvocellular pathway); and blue grating with yellow background adaptation: 200 milliseconds onset, 500 milliseconds offset (activation of the blue-sensitive pathway).

RESULTS

The glaucoma group and the control group differed significantly (P < 0.01) in the peak times of all chromatic VEP responses and to a lesser degree in the achromatic VEP. Considering the amplitudes, only the low-contrast red-green stimulus showed a statistically significant reduction in glaucoma. At a predefined specificity of 90%, in separating patients with glaucoma from healthy control subjects, the peak time of the blue-yellow VEP had a high sensitivity (90%), whereas the sensitivity of the achromatic VEP was low (31%). The red-green VEP showed a sensitivity of 73% using low contrast and 71% using high contrast. In a paired correlation analysis with visual field defects, all stimulations showed significant (P < 0.05) results. Correlation coefficients were highest (R = 0.79, P < 0.01) for the peak time of the blue-yellow VEP.

CONCLUSIONS

VEP measurements with presumable stimulation of single neuronal pathways can detect glaucomatous optic nerve damage in a considerable fraction of patients with visual field loss. Occipital responses to chromatic stimulation seem to be more sensitive to glaucoma damages than do responses to achromatic pattern reversal stimulation.

[Central corneal thickness in normal eyes, patients with ocular hypertension, normal-pressure and open-angle glaucomas--a clinical study]

BACKGROUND

The relation between Goldmann applanation tonometry and central corneal thickness (CCT) was investigated in several studies during the last thirty years. It was the aim of the present study to evaluate CCT in normals, patients with ocular hypertension, low-tension, and open-angle glaucomas.

PATIENTS AND METHODS

CCT was measured in 135 normal eyes, 137 with ocular hypertension, 65 with low-tension, and 94 with primary and secondary open-angle glaucomas using the AL-11000-pachymeter (Tomey). The results were compared using the unpaired t-test.

RESULTS

CCT was significantly higher in the patients with ocular hypertension (586 +/- 43 microns) than in the normal group (566 +/- 37 microns, p < 0.0001), in low-tension glaucomas (555 +/- 46 microns, p < 0.0001), and in open-angle glaucomas (558 +/- 31 microns, p < 0.0001). The latter three groups did not differ significantly. There was no significant correlation between CCT and age, the actually measured IOP, the highest IOP in the patient's history, or the spherical equivalent.

CONCLUSIONS

Only patients with ocular hypertension showed a significant difference in CCT compared with normals. Pachymetry thus should be conducted in those patients to avoid overestimation of the IOP by applanation tonometry. In most of the patients with low-tension and open-angle glaucomas however, CCT regarded without other parameters (e.g. corneal or scleral rigidity) plays a minor role in detection of elevated IOP according to the results of this study.

[Synopsis of various electrophysiological tests in early glaucoma diagnosis--temporal and spatiotemporal contrast sensitivity, light- and color-contrast pattern-reversal electroretinogram, blue-yellow VEP]

BACKGROUND

Of the three glaucoma-defining criteria intraocular pressure, optic-nerve damage, and visual field damage, the latter is a late symptom. Therefore, in order to improve an early sensory diagnosis, new tests are necessary. It is the aim of the present paper to test new sensory methods, to rank them in an order of sensitivity, and to base them on possible pathophysiological mechanisms.

PATIENTS AND METHODS

The tests were carried out in subjects of the Erlangen Glaucoma registry: Normals, patients with ocular hypertension, and patients with open-angle glaucoma without or with field defects. The tests are designed to preferentially probe the function of different groups of ganglion cells. Psychophysical methods: Temporal contrast sensitivity in a ganzfeld as "Erlangen flicker test" and spatio-temporal contrast sensitivity to test Magno-cell function. Electrophysiological methods: Pattern-reversal electroretinogram with a luminance-contrast pattern to test Magno-cell function, color-contrast pattern electroretinogram for Parvo-cell function, and blue-on-yellow visual evoked potential to test the "blue-sensitive" pathway.

RESULTS

The most sensitive test is the temp.CS, it is significantly reduced in OHT (p < 0.01). The spatio-temp.CS is reduced in perimetric stages (p < 0.01). The BY-VEP is altered in the preperimetric stage (p < 0.01), the PR-ERG in perimetric stages (p < 0.01). The CC-ERG is reduced in even later stages. These results are in agreement with the hypothesis that tests selective for non-redundant neurons are of early diagnostic value. Multivariate analyses increase the early diagnostic value when different functions are tested in combination.

CONCLUSIONS

When a particular test is taylored to the the special needs of certain groups of ganglion cells sensory defects can be observed before the occurrence of optic-nerve damage (OHT). The most sensitive psychophysical test is the "Erlangen flicker test" which is a screening test selective for M cells. The most sensitive electrophysiological test is the BY-VEP testing the blue-sensitive ganglion cells.

Ranking of optic disc variables for detection of glaucomatous optic nerve damage

PURPOSE

To describe optic disc variables assessed by evaluation of clinical optic disc photographs and to compare sensitivity and specificity of these optic disc parameters in identifying patients with ocular hypertension who have nerve fiber layer defects and normal visual fields and patients with visual field defects.

METHODS

The study included 500 normal subjects, 132 patients with ocular hypertension with retinal nerve fiber layer defects and normal visual fields (preperimetric glaucoma), and 840 patients with glaucomatous visual field defects. Color stereo optic disc photographs were morphometrically evaluated.

RESULTS

Highest diagnostic power for the separation between the normal group and the preperimetric glaucoma group had the vertical cup-to-disc diameter ratio corrected for its dependence on the optic disc size, total neuroretinal rim area, rim-to-disc area ratio corrected for disc size, and cup-to-disc area ratio corrected for disc size. Diagnostic power was lower for rim area in the temporal inferior and temporal superior disc sector, cup area corrected for disc size, and horizontal cup-to-disc diameter ratio corrected for disc size. Less useful for the differentiation between the normal subjects and the preperimetric glaucoma group were size of zones alpha and beta of parapapillary chorioretinal atrophy, and ratios of neuroretinal rim width and rim area comparing various optic disc sectors with each other.

CONCLUSIONS

In subjects with ocular hypertension with retinal nerve fiber layer defects and normal conventional achromatic visual fields, the vertical cup-to-disc diameter ratio corrected for optic disc size, total neuroretinal rim area, rim-to-disc area ratio, and cup-to-disc area ratio corrected for disc size are the most valuable optic disc variables for early detection of glaucomatous optic nerve damage. Correction for optic disc size is necessary for optic disc variables directly or indirectly derived from the optic cup. Parapapillary atrophy is less important in the early detection of glaucoma.

An early antecedent to modern random dot stereograms --'the secret stereoscopic writing' of Ramón y Cajal

The use of computerized random dot stimuli in modern neuroscience was introduced by Julesz in the 1960s. This method made it possible to study exclusively cortical processing of binocular information by disparity-sensitive neurons, and it has attained widespread use among neuroscientists and psychologists. It is now largely forgotten that in the last century, the famous neuroanatomist Ramón y Cajal had worked on random dot stereograms as a means of encoding written information. A brief note was finally published in a Spanish journal on photography in 1901. We present a translation of this text and summarize the early ideas on random dot stereograms, and we also supply a brief historical account on stereoscopic perception.

Nitrergic and VIPergic neurons in the choroid and ciliary ganglion of the duck Anis carina

Immunohistochemistry for neuronal nitric oxide synthase (nNOS) and vasoactive intestinal peptide (VIP), and NADPH diaphorase histochemistry, were applied to investigate neurons in the choroid and the ciliary ganglion of the muscovy duck Anis carina. Up to 1000 neurons in the choroid stained for NADPH diaphorase and showed virtually complete colocalization for nNOS immunoreactivity. Almost all of them co-stained for VIP, while about 90% of VIP immunoreactive cell bodies showed colocalization for nNOS. Two-thirds of the neurons were located, mostly singly, at nodes of a wide-meshed nerve plexus in the suprachoroid and were only rarely grouped in ganglia of up to 3 neurons. Numerous varicose nNOS/NADPH-diaphorase-positive nerve fibers were seen around large arterial blood vessels. These fibers derived mainly from paravascular cell bodies that represented about one-third of all choroidal neurons and also displayed costaining for nitrergic markers and VIP. Colocalization of nNOS/NADPH-d and VIP could be demonstrated in most of the perivascular fibers, while slightly more VIP-positive axons in the suprachoroid plexus did not costain for nNOS/NADPH-d. Small-caliber blood vessels and those localized in the choriocapillaris were not endowed with VIP/nNOS/NADPH-diaphorase-positive fibers. A few reactive neuronal cell bodies were also found in ciliary nerves, while most ciliary axons were unstained. In the ciliary ganglion a small subpopulation of neurons showed VIP/nNOS/NADPH-diaphorase colocalization. There were also nNOS/NADPH-d-positive cap-like terminals on ciliary ganglion cells. The presence of VIP/nNOS/NADPH-diaphorase positive neurons and nerve fibers in both the choroid and ciliary ganglion, and in the choroidal perivascular plexus, indicates peripheral nitrergic and VIPergic control of blood flow in the choroid of the duck.

[Nitrergic reactivity in endothelial cells of human uveal blood vessels]

BACKGROUND

We investigated the presence of Nicotinamid-adenin-dinucleotid-phosphat (NADPH)-diaphorase activity in endothelial cells of the human uveal vessels, using a histochemical procedure which presumably localizes the reaction product nitric oxide.

MATERIAL AND METHODS

11 donor eyes destined for corneal transplantation (male: 6; female: 5; age: 56 +/- 8 years) were used within 14 +/- 7 h postmorten. After removal of the cornea and retinal pigment epithelium, flat mounts of the choroid were made. Serial sections, 12-16 microns in thickness were cut from the ciliary body and iris using a cryomicrotome. Sections mounted on chromalaun-gelatine-coated glass slides, treated according the standard NADPH-diaphorase reaction and finally mounted in Kayser's glycerol-gelatine prior to examination in the light microscope.

RESULTS

Human choroidal vascular endothelial cells revealed positive NADPH-diaphorase activity, which was detected by the presence of punctate blue staining in the cytoplasm. No significant difference in distribution pattern or area density was seen amongst small and large vessels in either choroid, ciliary body or iris. Ganglion cells in the choroid and ciliary body also exhibited NADPH-diaphorase reactivity.

CONCLUSION

The presence of NADPH-diaphorase reactivity in vascular endothelial and ganglion cells of the human choroid suggests a possible nitrergic relaxation mechanism in human uveal vasculature.

["The Retina of the Vertebrates" by Santiago Ramón y Cajal--100 years in German translation]

1894 Richard Greeff, a young scientist at the University of Berlin, translated the book "The retina of vertebrates" of Santiago Ramón y Cajal into German. Greeff himself had already applied the Golgi-Cajal-Chromic-Silver dye to the retina and was enthusiastic about the results of Cajal. He interrupted his own investigations in favour of translating the book into German. Cajal demonstrates that the retina contains individual neurons contradicting the theory at that time, that the nervous system is a synzythium. This new theory had a great impact on German science although it took years to be accepted unanimously.

Visualization of human choroidal ganglion cells with the supravital fluorescent dye 4-(4-diethylaminostyryl)-N-methylpyridium iodide

The distribution and morphology of ganglion cell bodies and nerve fibers in supravital human choroidea is studied by staining with the fluorescent dye 4-(4-diethylaminostyryl)-N-methylpyridium iodide (4-Di-2-ASP). We have used the choroids from human donor eyes donated for cornea transplantation. The isolated tissues were rinsed in ringer solution and processed within up to 24 h after death with 3 microM of 4-Di-2-ASP in Ringer for 5-60 min at different temperatures (4-37 degrees C). After incubation, choroid whole flat mounts were observed in a fluorescence microscope. A delicate network of nerve fibers could be distinguished as soon as 5 min after immersion in 4-Di-2-ASP. In addition, labelled ganglion cell perikarya could be seen after longer incubation periods. They occurred individually or grouped in small ganglia of up to 8 cells and were linked together by various processes, which could also be traced to blood vessels. The fluorescent dye 4-Di-2-ASP provides a quick and simple method to visualize the innervation of the human choroid, including local ganglion cells. This nontoxic fluorescent technique will permit further manipulation and electrophysiological investigation of choroidal innervation.

[Unavoidable epistaxis in the nasal infestation of leeches]

An adult man is presented with a case of epistaxis due to leech (Limnatis linotica) intranasal parasitation. The geographical area where infection was performed is in the province of Teruel, northwest Spain. The only presented symptom was an incoercible nasal haemorrhage with low flow which didn't cease by anterior tamponade. 7 days after the process began he was heeded at the Emergency Service, Alcañiz Hospital, where the exam of left nasal fossa showed the presence of a olive-green long mass, very mobile. The treatment consisted on the leech extraction with a dissection forceps. Haemorrhage stopped immediately after the mild intervention and, reexamination the nasal fossa 15 days after, it was no wound or infectious complication observed. The patient was infested when drinking water from a fountain placed in rural area.

[NADPH-D reactive choroid ganglion cells in the human]

BACKGROUND

The demonstration of uveal ganglion cells has been investigated so far by silver impregnation, rather complicated neurohistochemical methods and by electron microscopy. We present the first results of a simple method in flat-preparation of the human choroid.

MATERIAL AND METHODS

Donors' eyes for cornea transplantation, 5 men, 3 women, aged 45 +/- 13 years, with postmortal time of preparation of 12 +/- 9 h (1 h-24 h) were used. After removal of the cornea with scleral ring, flat-preparations of the choroid were treated by the standard Nicotinamide-Adenine-Dinucleotide-Phosphate (NADPH)-diaphorase reaction, mounted on coated slides in Kayser's glycerol-gelatin and observed by light microscope.

RESULTS

NADPH-diaphorase reaction reveals abundant aggregates of ganglion cells, with nets of dendrites and axons in the otherwise unstained flat-preparation of the human choroidea. They are more abundant in the layer close to the sclera.

CONCLUSION

NADPH-diaphorase reaction is a simple method for the detection of ganglion cells in the human choroid. Their unexpectedly high number suggests yet unknown ganglional functions in the uvea.