Pathologic quiz case 2. Epidermoid cyst and thyroglossal duct (TGD) cyst.
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Biomedical subjects
Publications and source records attributed to C H Chang.
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A 24-year-old male patient who sustained blunt trauma to the chest resulting in a flail chest, myocardial contusion and injury to mitral valve is reported. An emergency surgical correction of the mitral lesion was performed. A high index of suspicion, prompt diagnosis and aggressive intervention of such injuries can lead to successful repair of such a potentially fatal cardiac trauma.
Renal calculi is an uncommon clinical presentation of parathyroid adenoma today. Only 17% of parathyroid adenoma has renal calculi in Levin's report. The association of parathyroid adenoma is often overlooked in the patients of renal calculi. We report a case whose clinical presentation is renal calculi with renal colic Parathyroid adenoma was not discovered until the second admission. The patient's clinical presentation improved after parathyroidectomy. We report this case to remind the clinical physician regarding the possibility of coexistence of parathyroid adenoma in patients of renal calculi. Excision of the parathyroid adenoma is the only treatment for these patients.
A 15-yr-old, Arabic male presented with painful, recurrent, self-resolving oral and genital ulcers, erythema nodosum and uveitis. Behcet's disease was diagnosed. A few months later, he experienced anorexia, abdominal pain, diarrhea, and weight loss. Although all routine laboratory and radiologic investigations were negative, colonoscopy revealed the presence of serpiginous ulcers with pseudopolyps and inflamed intervening mucosa in the proximal half of the colon. Therapy with oral steroids was helpful, but the disease exacerbated a few months after prednisone was discontinued. Repeat evaluation showed similar endoscopic findings and, on colonic biopsy, noncaseating granulomas compatible with Crohn's disease were seen. Again, the patient responded well to oral steroids and sulfasalazine. We believe that gastrointestinal involvement in our patient is compatible with Crohn's disease and that screening tests to rule out chronic inflammatory bowel disease should be performed in the presence of gastrointestinal involvement in Behcet's disease. Behcet's disease may be a part of the spectrum of chronic inflammatory bowel disease.
Available crystallographic data for homologous immunoglobulin constant domains were correlated with measured association constants for these domains. High correlation was found between the association constant and both the buried surface area (number of interdomain contacts) and the number of salt bridges formed in the interaction, whereas no correlation with the number of hydrogen bonds between domains was evident. The total free energy of binding, as determined from the association constant, was related to the number of contacts, hydrogen bonds and salt bridges found in the domain:domain interface by the crystallographic studies. These calculations yielded reasonable average energy terms for each interaction category.
Examination of oxidative metabolism in mitochondria isolated from quadriceps skeletal muscle biopsy specimens of 4 patients with Kearns-Sayre syndrome has shown that the mitochondria were tightly coupled, with maximal respiratory rates depending on the presence of adenosine diphosphate (ADP), Ca2+, or uncoupler. The state 3 respiratory rates with nicotinamide adenine dinucleotide (NAD)-linked substrates and succinate were much lower than those of control subjects. The cytochrome oxidase activities (measured with ascorbate + phenazine methosulfate as substrates) were also decreased, but this segment of the respiratory chain was not rate-limiting for succinate or NAD-linked substrate oxidation. Analyses of the steady-state reduction kinetics of the respiratory chain carriers revealed that the rate-limiting step of the impaired respiration with succinate or NAD-linked substrates lies between the c cytochromes and cytochrome oxidase. Measurement of the total substrate-reducible (at anaerobiosis) and chemically reducible levels of the cytochromes in mitochondria from 3 patients showed a severe deficiency of cytochrome a + a3 and an excess of the c cytochromes. To our knowledge, this is the first instance in which a mitochondrial electron transfer defect and cytochrome oxidase deficiency has been shown to be associated with an excess of the c cytochromes.
In a previous study, we used an enzyme-linked immunosorbent assay to measure soluble human interleukin-2 receptors (IL-2R), and found that when activated lymphocytes produce cell-associated IL-2R, they also release a soluble form of IL-2R into culture supernatants in vitro. Soluble IL-2R have also been detected circulating in vivo at low levels in the serum of healthy individuals, and at abnormal levels in a variety of diseases, particularly those where immune dysfunction is thought to play an important role. We therefore evaluated serum IL-2R levels in 77 patients with rheumatoid arthritis (RA), and compared them with levels in 46 age-matched healthy controls. Nineteen additional RA patients with concurrently obtained sera and synovial fluid (SF) samples were compared with 14 patients with osteoarthritis of the knee or hip. The serum IL-2R levels were significantly elevated in RA patients, compared with the control groups (P less than 0.0001). Serum IL-2R levels in the RA patients did not correlate with disease activity as determined by a variety of clinical and laboratory parameters. RA SF IL-2R levels were significantly higher than corresponding RA serum IL-2R levels (P = 0.0001). No such difference was noted in the osteoarthritis group, where serum and SF IL-2R levels were comparable with serum levels in healthy controls. These findings support the hypothesis that in vivo lymphocyte activation plays an important role in RA; moreover, soluble IL-2R measurement in serum and SF may be a very useful way to identify patients at risk for, or manifesting, a chronic immune-mediated inflammatory arthropathy.
Primary tumors of the heart are infrequent at all ages. We present a newborn with hypoxia and a heart murmur, in whom an echocardiogram revealed a large tumor filling the right ventricle and the pulmonary annulus. To maintain pulmonary blood flow, the patency of the ductus arteriosus was achieved by infusion of prostaglandin E1. Successful surgical resection was accomplished. The pathological examination was characteristic of a benign teratoma. The patient remains asymptomatic and has shown no evidence of recurrence of the tumor during a follow-up period of 34 months. This represents the eleventh case of intracardiac teratoma and only the fourth case to undergo successful surgical resection.
The clinical and pathological features of primary pulmonary artery sarcoma in two children are reported. The first patient presented with right ventricular outflow obstruction and underwent successful surgical resection of his tumor. The second patient developed cardiac arrest following a relatively short period of symptoms of right heart failure and could not be revived. The pathological diagnosis in both patients was hemangiopericytoma. To the best of our knowledge, primary pulmonary artery sarcoma in children has not been previously reported.
Doppler, contrast, and two-dimensional echocardiograms of 12 aneurysms of the sinus of Valsalva in 10 consecutive patients were analyzed in order to highlight the diagnostic features. The diagnosis were confirmed by surgical and/or catheterization findings. The aneurysms had ruptured in 7 of 12 (58%). Two-dimensional echocardiography prior to the contrast studies was able to delineate the aneurysms in 7 of 12 (58%). The contrast studies outlined two additional aneurysms. The right aneurysms directed anteriorly and caudally. The noncoronary aneurysms formed an extraneous lumen at the posterior part of the aortic root, mimicking aortic dissection. Doppler examinations showed systolic and diastolic turbulence in five of six (83%) of the right aneurysms rupturing into the right ventricular outflow tract. Color Doppler echocardiography showed a left ventricular diastolic turbulence emanating from the aneurysm in a case with a noncoronary aneurysm rupturing into the left ventricle. It is concluded that the principal Doppler, contrast, and two-dimensional echocardiographic features usually allow a rapid correct diagnosis of sinus of Valsalva aneurysm.
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A plasmid DNA library was constructed from restriction endonuclease digested genomic deoxyribonucleic acid (DNA) of a virulent strain of Mycobacterium tuberculosis isolated from sputum of a patient. The sensitivity and specificity of two of the cloned DNA fragments in detecting M. tuberculosis and its related DNA sequences were analysed by DNA-to-DNA hybridization. The level of detection was determined to be 50 picograms of M. tuberculosis DNA, which is approximately equivalent to 10,000 mycobacterial genomes. These two M. tuberculosis DNA probes did not cross-hybridize to DNA of non-mycobacterial origin, nor with DNA from 9 out of 11 other mycobacterial species. Mycobacterial DNA sequences could be detected in 134 of 441, or 30.4%, of various types of uncultured clinical specimens from 365 patients by the DNA probes, whereas traditional culture method showed only a 19.0% positivity rate for the same specimens (p less than 0.001). The overall sensitivity and specificity of the DNA probes in detecting M. tuberculosis are 90.5% and 83.8% respectively. The DNA hybridization test may become a useful tool for the early and rapid determination of mycobacterial infection in uncultured clinical specimens.
In 24 patients, corrosive injuries involving the floor of the mouth, the pharynx, and the esophagus were repaired in two stages using a combined free forearm flap and colon for functional restoration of the alimentary tract. The results were satisfactory. Morbidity was decreased, complications were minimal, and there were no failures. In the first stage, early reconstruction with a forearm flap for the oral floor, the pharynx, and the cervical esophagus can be done safely 3 months after the original injury when the acute inflammation of the tissue has disappeared. The forearm flap is thin and pliable, and has a good blood supply for primary healing without failure or stricture. Dysphagia is eliminated because food passes down by gravity. There is no constriction or hyperperistalsis of the colon, both of which are occasionally seen with the traditional colon interposition. In the second stage, the traditional method is used to finish the reconstruction of the remainder of the esophagus.
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The structure of an immunoglobulin antigen-binding fragment (Fab) has been thought to be invariantly defined by well-conserved amino acid residues in the variable domains of the heavy and light chains. These conserved residues enable folding of the polypeptide segments into the characteristic immunoglobulin fold domains and are the major controllers of interactions between domains. However, crystallographic studies of some immunoglobulin light-chain dimers have suggested and the crystallographic structure of the Fab in an Fab-neuraminidase complex may have proven that antibodies are not restricted to a single, invariant relative positioning of the two variable domains. We propose that in some cases the detailed quaternary structural relationships between the variable domains of heavy and light chains are not restricted to those of the canonical Fab. It is unclear whether alterations of these relationships occur only after complex formation with antigen or, if in ligand-free solution, Fab conformers might coexist in relative concentrations determined by isomerization rates. In the latter case, antibody-presenting lymphocytes may be polyspecific, and the specificity of lymphocytes might be modulated by anti-idiotopic antibodies complexed to cell surface receptors. In either case, the idiotopic repertoire displayed by an antibody or lymphocyte surface receptor might be changed by the presence or absence of antigen.
The interactions of the nitrovasodilators, endothelium-dependent vasodilators, and atrial peptides with cGMP synthesis have proved to be useful and important leads to the functions of cGMP and signal transduction mechanisms. Although considerable progress has been made, many important questions remain to be answered. Nevertheless, the guanylate cyclase-cGMP system clearly represents an important second-messenger system that mediates the effects of numerous agents.
Thirty cases of multicystic dysplastic kidney (MCDK) were diagnosed over 11 years. Nine patients underwent nephrectomy: three for increasing kidney size (classic MCDK) and six because of an inconclusive diagnosis (hydronephrotic MCDK). Of the remaining 21 patients, 19 were followed up for a mean of 33.5 months (range, 2-101 months). Follow-up ultrasound examinations revealed that 16 kidneys did not change in size, one decreased in size after cyst puncture, and two disappeared (one after cyst puncture). This series included one case of non-renin-producing hypertension that was controlled medically, one case of nephroblastomatosis found in the removed dysplastic kidney, and one case of pyelonephritis in the contralateral kidney. When the diagnosis of classic MCDK is made with imaging modalities, the lesion may not have to be removed unless there is growth of the mass during the 1st year of life. Nine percent of these lesions will disappear within the first 3 years of follow-up, and the authors recommend an even longer period of follow-up.