Aetiology of keratoconus

Keratoconus has a common association with atopic conditions. Most keratoconus patients rub their eyes excessively. Eye-rubbing is considered the dominant aetiological factor in two-thirds of patients with keratoconus who progress to contact lens wear. A classification of keratoconus based on the dominant aetiological factors is proposed. No significant psychoneurotic factor was found in the keratoconus patients compared with patients in the control group.     

Aetiology of haemospermia

There are several unknown factors which cause haemospermia. An earlier developed diagnostic scheme has been expended by novel imaging techniques and biopsy methods. A detailed case history, physical examination and microscopic analysis of the ejaculate is required. In haemo-pyospermia a complete microbiological analysis must be escalated. Noninvasive imaging techniques (ultrasound, computer tomography and magnetic resonance imaging) help in detecting calculous and malignant diseases. So far, as a precise diagnosis has not been available, urethroscopy has been performed. Malignancies (prostate, seminal vesicles) must be histologically verified by biopsies. In contempt of our efforts the practice shows a part of haemospermia remaining essential. Analysing two time periods we found prostatic calculi, chronic prostatitis and carcinoma of the prostate unequivocally as most frequent causes. Considering the rare genital malignancies we find more than 10% frequency. Notably, in our study only 2.4% of the malignancies occurred in patients under 40 years of age. Hence a detailed diagnosis is advocated in haemospermia patients over 40 years. Finally, we may state that in contempt of the applied modern imaging techniques 15% of patients with haemospermia had unknown aetiology.     

Aetiology of oral cancer: alcohol

This prospective cohort study determined the incidence and risk factors for development of postdural puncture headache (PDPH) in children after lumbar puncture (LP). Eighty-six children were enrolled. LPs were performed with use of 22-gauge spinal needles with the bevel oriented parallel to the long axis of the spine. Follow-up telephone interviews and patients' diary of symptoms were collected. Headache brought on by sitting up and relieved by lying down was defined as PDPH. Of the 80 who completed the study, six (8%) developed PDPH. Two (3%) were less than 6 years old and four (5%) were 6 to 12 years of age. Children with a history of headache following a previous LP were nine times as likely to experience PDPH. PDPH occurs not infrequently in children. A prior history of headache is a predisposing factor.     

Aetiology of deafness in white children in the Cape

Two-hundred and forty White children attending special schools for the deaf have been investigated by clinical,genetic and laboratory methods in order to determine determine the aetiology of their hearing disability of these, 36% had a genetic basis for their deafness, while in a further 34% an acquired lesion was incriminated. The most important determinants of acquired deafness were maternal rubella, neonatal hyperbilirubinaemia and meningo-encephalitis. The prevention of childhood deafness is primarily dependent upon recognition of the underlying causative factor.     

Aetiology and Pathogenesis of abomasal displacement in dairy cattle

A clinical chemical survey is given of the complex of factors which are involved during development of clinically manifest hypotony or atony of the abomasum prior to abomasal displacemnts. The importance of a change in the acid-base balance of the animals is especially stressed as a predisposing factor. The further pathogenesis of abomasal displacement is supposed to follow different ways, according to the feeding and to prevailing periods of indigestion.     

Aetiology of acute diarrhoea in hospitalized children in Hong Kong

To determine the role of enteric pathogens in acute childhood diarrhoea in Hong Kong, 388 children with diarrhoea and 306 children of similar age without diarrhoea were evaluated in a hospital-based study during a one-year period from August 1994 to July 1995. Of the diarrhoeal cases, 55% were under 1 year and 95% were below 5 years of age. On admission, 22% had some dehydration but none was severely dehydrated. All children were well nourished. Oyer 60% of children with diarrhoea had one or more pathogens in their stool. Rotavirus was the most commonly isolated pathogen (34.6%), followed by Salmonella (23.3%), Campylobacter (4.7%) and Shigella (2.1%). Rotavirus was not assessed in the controls and was detected mainly during the winter months December to February. Bacterial pathogens were identified more commonly in diarrhoea patients (30%) than in controls (5.6%) (P < 0.001). Despite rapid recent socioeconomic development in Hong Kong, non-typhoidal Salmonella diarrhoea remains a significant local problem in infants under 1 year. Further detailed assessment of the transmission and prevention of this infection is required.     

Permanent open shunt as a reason for impotence or reduced potency after surgical treatment of priapism in 26 patients

A permanent open shunt as a cause of impotence or impaired potency after a shunt operation for priapism is an unusual situation. In this series we studied the persistence of an open shunt in 26 patients who had developed impotence or impaired potency after operative treatment for priapism. All patients had been examined by cavernosography on the suspicion of an open shunt, giving a positive finding in five of 26 cases, in all of which impotence was cured by closure of the shunt. In five patients without a permanent open shunt potency returned to normal only after 6-12 months.     

Aetiology of nasopharyngeal carcinoma. A review

The present overview is based on recent available information on nasopharyngeal carcinoma (NPC) from various parts of the world including India. The available data suggests that NPC is a rare tumour in most parts of the world. But the incidence is higher in China and South East Asia and also among the Chinese wherever they have migrated. NPC is also relatively higher especially among the mongoloid group of the people in the North Eastern Region of India as compared to other parts of the country. The distinct geographical and ethnic distribution of NPC have stimulated much research to find out its etiology. The results suggest that Epstein Barr Virus (EBV) infection and genetic susceptibility are the constant aetiological factors for the higher incidence of NPC among various ethnic groups while other factors such as ingestants and inhalants may depend on the distinct dietary practices and living environment adopted by various ethnic groups in different geographical region of the world.     

Aetiology and pathogenesis of alcoholic liver disease

Until the 1960s, liver disease of the alcoholic patient was attributed exclusively to dietary deficiencies. Since then, however, our understanding of the impact of alcoholism on nutritional status has undergone a progressive evolution. Alcohol, because of its high energy content, was at first perceived to act exclusively as 'empty calories' displacing other nutrients in the diet, and causing primary malnutrition through decreased intake of essential nutrients. With improvement in the overall nutrition of the population, the role of primary malnutrition waned and secondary malnutrition was emphasized as a result of a better understanding of maldigestion and malabsorption caused by chronic alcohol consumption and various diseases associated with chronic alcoholism. At the same time, the concept of the direct toxicity of alcohol came to the forefront as an explanation for the widespread cellular injury. Some of the hepatotoxicity was found to result from the metabolic disturbances associated with the oxidation of ethanol via the liver alcohol dehydrogenase (ADH) pathway and the redox changes produced by the generated NADH, which in turn affects the metabolism of lipids, carbohydrates, proteins and purines. Exaggeration of the redox change by the relative hypoxia which prevails physiologically in the perivenular zone contributes to the exacerbation of the ethanol-induced lesions in zone 3. In addition to ADH, ethanol can be oxidized by liver microsomes: studies over the last twenty years have culminated in the molecular elucidation of the ethanol-inducible cytochrome P450IIE1 (CYP2E1) which contributes not only to ethanol metabolism and tolerance, but also to the selective hepatic perivenular toxicity of various xenobiotics. Their activation by CYP2E1 now provides an understanding for the increased susceptibility of the heavy drinker to the toxicity of industrial solvents, anaesthetic agents, commonly prescribed drugs, 'over the counter' analgesics, chemical carcinogens and even nutritional factors such as vitamin A. Ethanol causes not only vitamin A depletion but it also enhances its hepatotoxicity. Furthermore, induction of the microsomal pathway contributes to increased acetaldehyde generation, with formation of protein adducts, resulting in antibody production, enzyme inactivation and decreased DNA repair; it is also associated with a striking impairment of the capacity of the liver to utilize oxygen. Moreover, acetaldehyde promotes glutathione depletion, free-radical mediated toxicity and lipid peroxidation. In addition, acetaldehyde affects hepatic collagen synthesis: both in vivo and in vitro (in cultured myofibroblasts and lipocytes), ethanol and its metabolite acetaldehyde were found to increase collagen accumulation and mRNA levels for collagen. This new understanding of the pathogenesis of alcoholic liver disease may eventually improve therapy with drugs and nutrients.     

Multisystem damage associated with tricorporal priapism in sickle cell disease

It is demonstrated that fowlpox virus (FPV) protein FP26 located in the HindIII D fragment of the genome is related to the human deoxycytidine kinase (dCK) and probably possesses the same enzymatic activity. A homologous protein is not encoded by vaccinia virus. A multiple alignment of the amino acid sequences of the human and FPV dCKs, the thymidine kinases (TK) of herpesviruses, and cellular and vaccinia virus thymidylate kinases (ThyK) was generated and the conserved motifs, at least two of which are implicated in ATP binding, were characterized. An apparent duplication of ATP-binding motif B in the dCKs was revealed, leading to the reassignment of one of the catalytic residues. Phylogenetic analysis based on the multiple alignment suggested that the putative dCK of FPV probably has diverged from the common ancestor with the human dCK at a later stage of evolution than the herpesvirus TKs, with the ThyKs being peripheral members of the family. These results are compatible with hypothesis that genes for enzymes of nucleotide metabolism could be acquired independently by different DNA viruses (Koonin, E.V. and Senkevich, T.G., Virus Genes 6:187-196, 1992).     

Posttraumatic priapism in a 6-year-old boy: a case report

A 6-year-old boy showed priapism after blunt perineal trauma. We diagnosed him with venous priapism mainly based on clinical symptoms, although we could not deny an arterial type. In fear of possible erectile dysfunction as a late complication of the venous type, we performed a shunt operation. The shunt was created between glans penis and corporacavernosa, resulting in disappearance of priapism and preservation of erectile function. We also reviewed 14 cases reported previously.     

Erythropoietin-induced recurrent veno-occlusive priapism associated with end-stage renal disease

A longitudinal study of 21 pregnant women has been undertaken using a variety of factor VII assays, including factor VIIa, to investigate the increase of factor VIIc. All assays demonstrated significant rises (p <0.001), most marked for factor VIIa (82%) and factor VIIc rabbit (81%). Smaller rises were seen for factor VIIc bovine (50%) and VII antigen (40%). Three indirect measures of activity state, factor VIIc rabbit:antigen, bovine:antigen and bovine:rabbit, provided conflicting data. Factor VIIa:antigen showed a significant increase of 36% (p <0.001). Within individual pregnancies the change in factor VIIc rabbit and antigen correlated with maternal weight gain (p < 0.05). Two activity state measures, bovine:rabbit and bovine:antigen, showed negative correlation with birthweight. The increases in both zymogen and in activity state appear to contribute to the factor VIIc rise. The extent of this rise appears to be influenced by maternal weight gain. Increased factor VII activation is associated with reduced foetal growth.     

High-flow priapism following blunt perineal trauma. Interventional therapy

With the increase of ischemic diseases of the circulatory system in Japan, the necessity for cardiovascular intervention continues to increase. However, because intervention operations have been developed only recently, the education system for the corresponding specialists in our country has not been established yet. In this study, an intervention educational support system using a virtual reality (VR) technique was developed. Of course, intervention includes percutaneous transluminal coronary angioplasty (PTCA). PTCA is an operation enlarging the stenosis of the coronary artery with a balloon through a guide catheter. The technique that lets the guide wire for the PTCA balloon cross the stenosis is one of the most difficult. A simulation system for the manipulation of a torque device for the PTCA guide wire was developed with this technology for VR. In virtual space, reconstitution of the 3-dimensional coronary artery with atherosclerosis was performed, and the virtual PTCA system was produced experimentally. An interesting system was produced experimentally as a system for the training of doctors studying to become interventional specialists. After the system was combined with an Expert system for treating ischemic heart diseases, its usefulness was steadily increased. With the development of more sophisticated VR methodology in the future, a PTCA training system without using a patient will be embodied.     

Venous leg ulcers. Part 1: Aetiology

Cardiogenic pulmonary edema is a frequent cause of reparatory failure. We investigated the effects of nasal continuous positive airway pressure (CPAP) in patients with severe pulmonary edema associated with acute myocardial infarction. Twenty-nine consecutive patients were divided into 3 groups: firstly, 7 intubated patients who received mechanical ventilation at study entry comprised the intubation group. The rest of the patients were randomly assigned to either of the following 2 groups: 11 patients who received oxygen plus CPAP delivered by a nasal mask (CPAP group), and 11 patients who received oxygen only via face mask (oxygen group). All patients in the intubation group had cardiogenic shock. Two patients (18%) in the CPAP group and 8 patients (73%) in the oxygen group required mechanical ventilation with endotracheal intubation (p=0.03). The hospital mortality rate in the CPAP group (9%) was significantly lower than the oxygen group (64%, p=0.02). The pulmonary artery wedge pressure and heart rate were significantly lower in the CPAP group than in the oxygen group 24 h after study entry (p<0.05 and p<0.01). The mean pulmonary artery pressure 48 h after study entry was 18+/-5 mmHg in the CPAP group and 25+/-8 mmHg in the oxygen group (p<0.05). The PaO2/FiO2 ratio increased in the intubation group (168+/-69 to 240+/-57, p<0.05) and the CPAP group (137+/-17 to 253+/-67, p<0.01) 24 h after study entry. Arterial plasma endothelin-1 concentrations decreased significantly earlier in the CPAP group than in the oxygen group (p<0.05). In patients without cardiogenic shock, nasal CPAP lead to an early improvement in oxygenation and hemodynamics, and decreased the mortality rate. Early and active respiratory management is recommended in patients with pulmonary edema associated with acute myocardial infarction.     

Aetiology, cost of antimicrobial therapy and outcome in neutropenic patients who developed bacteraemia during antimicrobial prophylaxis: a case-control study

The authors describe one case of purely epithelioid schwannoma of the ulnar nerve and discuss the therapeutic management. A 44 year-old man was referred to us for a fusiform, movable mass in the left ulnar nerve and was removed by a wide en bloc excision. Intraoperative nerve action potentials were performed both prior to and following excision of the lesion. Histologically, the tumor was composed of round or polygonal cells arranged in necrotic clusters and anastomosing cords. There were areas of spindle cells. The epithelioid cells were round with abundant cytoplasm. Mitoses were frequent. S100 protein immunoreactivity was present diffusely in tumor cells (both nuclear and cytoplasmic), whereas cytokeratin, NSE, and anti-melanoma reactions gave negative results. After a 13 months, the patient's neurological conditions are excellent and there are no signs of either recurrence or metastasis.