Preexisting Cysts Research Articles

Pneumatosis cystoides intestinalis in a trauma patient presenting with pneumoperitoneum: a case report

BackgroundPneumatosis cystoides intestinalis is a rare and usually benign condition in which multiple thin-walled cysts develop in the submucosa or subserosa of the gastrointestinal tract. While usually asymptomatic, severe cases can result in pneumoperitoneum, which can be managed surgically or medically depending on circumstances. We present a case of a patient with pneumatosis cystoides intestinalis, which presented as pneumoperitoneum following trauma. To our knowledge, there are no other published cases in which a trauma patient with pneumoperitoneum was found to have radiologic evidence of pneumatosis cystoides intestinalis.Case presentationWe present the case of a 37-year-old Hispanic male admitted to the hospital after being involved in a motorcycle accident. Computed tomography imaging of the abdomen and pelvis with oral and intravenous contrast demonstrated trace pneumoperitoneum, possibly originating from the splenic flexure of the colon without evidence of extravasation of oral contrast. Laparoscopy with conversion to exploratory laparotomy revealed bowel abnormalities at the distal transverse colon and splenic flexure, which were identified as pneumatosis cystoides intestinalis by pathology. There was no evidence of bowel perforation. A panel of abdominal radiologists attended the computed tomography interpretation to note that incidental atraumatic or traumatic rupture of the cysts could have caused the pneumoperitoneum. The patient had an uncomplicated postoperative course and was transferred to another facility per insurance request.ConclusionsWhen presenting in the context of trauma, pneumatosis cystoides intestinalis can lead to difficult management decisions. To our knowledge, there are no existing evidence-based guidelines for the scenario of concurrent pneumatosis cystoides intestinalis, blunt abdominal trauma, and pneumoperitoneum in a patient with a benign abdominal exam. This patient’s pneumoperitoneum was likely caused by rupture of preexisting cysts rather than frank bowel perforation. Patients who are asymptomatic, lack signs of clinically worrisome disease, and have a low pretest probability will likely not benefit from surgery and can be medically managed. Thorough discussion between surgeons and radiologists can be helpful when evaluating the clinical significance of a patient’s pneumatosis cystoides intestinalis and aid in the decision to perform surgery.

Infected simple renal cyst due to Streptococcus pneumoniae rapidly diagnosed by the melting temperature mapping method: a case report

BackgroundSpontaneous infection of preexisting solitary renal cysts has been documented in adults but is extremely rare in children. To date, no cases of simple renal cysts infected with Streptococcus pneumoniae have been described. Recently, reports have described the diagnosis of bacterial infection using the 16 S rRNA gene as well as the accompanying antimicrobial stewardship for microorganisms that are difficult to culture and for culture-negative cases after preceding antibacterial administration.Case presentationA four-year-old Japanese girl who had a pleuroperitoneal shunt inserted to drain a right pleural effusion due to occlusion of the hepatic portion of the inferior vena cava at three years old visited our hospital due to fever and respiratory discomfort. She was incidentally found to have a right simple renal cyst 10 months before admission. The patient was suspected to have pneumonitis or catheter-related blood stream infection on chest X-ray, which showed right-side pleural effusion. She was diagnosed with invasive pneumococcal infection, as Streptococcus pneumoniae was detected from blood culture on admission. Transient improvements in her symptoms and decreases in the white blood cell count and C-reactive protein level were observed after effective antibiotic administration, but her respiratory condition deteriorated. Enhanced CT showed right renal cyst enlargement and enhancement and thickening of the surrounding wall. Using the melting temperature (Tm) mapping method, S. pneumoniae was rapidly detected directly from pus 4.5 hours after drainage. The specimen culture was negative, but the extracted 16 S rDNA sequence revealed 100 % identity for S. pneumoniae from the same specimen the subsequent day. We successfully performed optimal treatment and reduced medical cost based on the positive Tm mapping method result.ConclusionsWe report the first case of a S. pneumoniae-infected simple renal cyst. The drainage culture was negative, but the Tm mapping method rapidly detected S. pneumoniae directly from the drainage. The Tm mapping method may have great impacts on rapid diagnosis and effective antimicrobial stewardship.

Long-Term Outcomes of Sporadic Vestibular Schwannomas Treated with Recent Stereotactic Radiosurgery Techniques

Vestibular schwannomas (VSs) are benign; thus, understanding long-term tumor control and late adverse radiation effects of stereotactic radiosurgery (SRS) through current radiosurgical techniques is important to inform treatment decisions. Our aim was to clarify long-term tumor control rates and incidence of late adverse radiation effects in patients with VSs followed for 5 years or longer after SRS. Altogether, 615 patients with VSs (excluding neurofibromatosis type 2 and partially treated tumors) followed for 5 years or longer after SRS using recent radiosurgical techniques were evaluated. All patients were treated at a margin dose of less than 14 Gy. All tumors were classified into 4 categories: type A (intracanalicular tumor, 87 patients [14%]), type B (cerebellopontine angle [CPA] tumor, 325 patients [53%]), type C (CPA tumor compressing the brain stem, 138 patients [22%]), and type D (CPA tumor compressing the brain stem with a deviation of the fourth ventricle, 65 patients [11%]). Median tumor volume was 2.0 cm3 and median marginal dose was 12 Gy. Median follow-up period was 158 months. Actuarial 5-, 10-, and 15-year or longer local control (LC) rates were 93%, 91%, and 89%, respectively. Tumor type (P < .001, hazard ratio 2.389) and number of prior surgeries (P = .007, hazard ratio 1.698) were significant for LC. Depending on the tumor type, the actuarial 10-year LC rates were 100%, 93%, 88%, and 70% in type A, B, C, and D tumors, respectively. No patient developed persistent facial palsy. Twenty patients (3.3%) developed delayed cysts. One patient developed malignant transformation (0.2%). SRS is a safe and effective treatment for VSs in the long term, excluding VSs compressing the brain stem witha deviation of the fourth ventricle. Delayed cysts such as cyst formation, enlarged preexisting cysts or extratumoral cysts, and malignant transformation should be considered possible causes of long-term treatment failures.

Primary squamous cell carcinoma of the liver: an unexpected pathological finding

BackgroundPrimary squamous cell carcinoma of the liver is a very rare cancer requiring a complete diagnostic investigation, as it presents some differences from other primary hepatic malignancies. We describe the case of an elderly patient with primitive squamous cell carcinoma of the liver treated by percutaneous microwave ablation and transarterial chemoembolization.Case presentationAlthough the pathogenesis remains uncertain, a possible transformation of the biliary epithelium caused by chronic inflammation or metaplasia and subsequent malignant transformation of preexisting benign hepatic cysts has been suggested. A critical review of the existing literature was performed by focusing on the pathogenesis, clinical presentation, and the suggested therapeutic strategies.ConclusionA multidisciplinary approach is needed to face rare hepatic malignancies where there are no clear guidelines.

Nontraumatic warfarin-related intrapulmonary hemorrhage presenting as a lung mass

BackgroundAlthough bleeding events are the major concern when using oral anticoagulants, intrathoracic hemorrhages due to warfarin are rare. Most cases in the literature have been related to trauma and have manifested as a hemothorax. Here we report a case of a nontraumatic hemorrhage within a pre-existing pulmonary cyst that presented as a lung mass during warfarin therapy.Case presentationA 75-year-old asymptomatic woman presented with a 10-cm-diameter mass on chest radiography that was not evident 6 months prior. She had been taking warfarin for paroxysmal atrial fibrillation and a transient ischemic attack. There was no history of chest trauma, warfarin overdosing, or any suspected interactions with other drugs such as nonsteroidal anti-inflammatory drugs or antibiotics. The prothrombin time/international normalized ratio(PT-INR) was prolonged at 4.73 and her hemoglobin level was 8.7 g/dl. Chest computed tomography(CT)revealed an air-fluid mass adjacent to the right upper and middle lobes with a pleural effusion. A CT scan obtained 15 years prior revealed a cyst at the corresponding site and the mass was diagnosed as a warfarin-related hemorrhage within the pre-existing pulmonary cyst. We performed a surgical resection of the cyst to prevent any worsening hemorrhage and subsequent infection. The postoperative course was uneventful and the patient was discharged on the 3rd postoperative day.ConclusionA warfarin-related thoracic hemorrhage, other than a hemothorax, could manifest as a pulmonary mass on radiography in patients with pre-existing pulmonary cysts. History taking especially of any anticoagulant medications and a precise assessment of the past images are crucial for a correct diagnosis. Once the intrapulmonary cystic hemorrhage becomes evident, prompt withdrawal with a reversal of warfarin and surgical resection are required to prevent a worsening hemorrhage and subsequent infection.

Renal cyst formation in patients treated with crizotinib for non-small cell lung cancer—Incidence, radiological features and clinical characteristics

Treatment with the ALK inhibitor crizotinib has been associated with complex renal cyst formation in patients with non-small cell lung cancer (NSCLC). Using patients treated with crizotinib, we aimed to evaluate the incidence of renal cyst formation, to identify risk factors for cyst formation and to provide a radiological description of cyst characteristics. Patients with ALK-positive NSCLC treated with crizotinib were retrospectively identified from an institutional database. Computed tomography (CT) imaging performed prior to and during crizotinib treatment was retrospectively reviewed to assess the size and complexity of pre-existing cysts, new cysts, and enlarging cysts. Demographic data including age, sex, ethnicity, smoking history and length of treatment were also recorded. Data from 60 patients with NSCLC treated with crizotinib at our institution between 6/5/2009 and 7/1/2015 were collected. 57 had CT imaging before and during treatment. Mean length of imaging follow-up was 18 months. 9 (16%) patients had cysts which enlarged or developed de novo during treatment. 2 (4%) patients developed complex renal cysts (1 of these patients also developed complex hepatic cysts). Female gender (p=0.008) and the presence of renal cysts on baseline scans (p=0.044) were significantly associated with cyst formation or growth. Renal cyst formation or growth occurred in 16% of crizotinib-treated patients. Women and those with pre-existing cysts were at greatest risk. Although the potential causal relationship between crizotinib use and renal cyst formation has yet to be fully defined, it is important for radiologists and clinicians to be aware of this finding.

Idiopathic scrotal calcinosis

Idiopathic scrotal calcinosis (ISC) is a rare and benign disorder first described by Lewinski in 1883. It is characterized by the presence of multiple yellowish-white calcified asymptomatic nodules gradually increasing in size, appearing in the scrotal skin. It appears mainly in men aged 20–40 years. Histopathology ISC reveals calcium deposits within the dermis that may be associated with giant cell reaction. The calcified intradermal nodules that are seen in this condition occur in the presence of normal calcium and phosphate metabolism. Many studies done on this entity spanning over the past years have failed to demonstrate its origin. Though few studies suggest this entity to be a result of dystrophic calcification in a preexisting cyst, many other studies failed to demonstrate histological evidence to the same. Hence, whether this condition is idiopathic or as a result of dystrophic calcification of preexisting cysts including epidermal, eccrine epithelial cyst, or degenerated dartos muscle remains a controversial issue. Associations with connective tissue diseases such as scleroderma, dermatomyositis, and systemic lupus erythematosus have also been known. Surgical excision is the gold standard treatment for this disease. We report two cases, one in a 59-year-old and other in a 47-year-old male, with no known comorbidities, both presenting with asymptomatic multiple hard scrotal nodules. Both the cases revealed dermal deposits of calcium with normal serum calcium and phosphate levels. There was no evidence of keratinous material, epithelial-lined cystic spaces, or preexisting duct-like structures within or around the foci of calcification, suggesting this entity to be distinct from dystrophic calcification in a preexisting cyst. Surgical excision was done with no evidence of recurrence.

Immediate Implant Placement in the Infected Site with Presence of a Pre-Existing Cyst: Report of Two Cases

Aim: The purpose of this report is to illustrate the possibility of inserting immediate implants into the fresh extraction sockets in the infected site with presence of a pre-existing cyst. Presentation of case: The 1 of two cases: A 31-year-old man, presented to severe periodontitis with presence of a pre-existing infected cysts developed, which was 5mm × 7mm on the labial side of mandible. The radiography showed that a large translucent image around the periapical portion of 31 with mobility of II° in mandible. The extraction and implantation including bone grafting to substitute 31 tooth had been performed in one appointment. One implant (14mm length × 3.7mm in diameter SIN implants Dentis, made in Korea) was inserted apically through a cyst cavity. Three months later, the second surgery phase (healing screw insertion) had been followed, and no sign of alternation of radiography and clinical indication after 18 months. The other, a 53-year-old man came to our attention, with presence of a pre-existing infected cyst on labial side of 42 tooth. We placed one implant in the infected position of the mandible with a small amount of heterologous bone after the elimination of the infected 42 tooth, the meticulous cleaning, and alveolar debridement. A second surgery phase had been done after three months. Discussion and conclusion: This report showed that the placement of immediate implants in presence of a pre-existing infected cyst may not be necessarily contraindicated if appropriate clinical procedures like antibiotic administration, meticulous cleaning, and alveolar debridement are performed before implant surgical procedure. Immediate placement of implants for replacement of teeth with the pre-existing infected cysts is a predictable treatment and can be indicated for replacing teeth lost. This report regards the immediate placement of an implant into a residual cyst; some anatomical, surgery techniques, clinical and pathological considerations arise from this case. Both implants were successfully osseointegrated, and the cysts were healed.

Complex renal cysts associated with crizotinib treatment.

An apparent causal association between crizotinib treatment and renal cyst development emerged during clinical trials in anaplastic lymphoma kinase (ALK)-positive non–small cell lung cancer (NSCLC). Serious adverse event (SAE) reports of renal cysts from a safety database of 1375 patients from four clinical trials were reviewed. A blinded, retrospective, independent radiologic review (IRR) was performed using scans from patients on study for ≥6 months in three clinical trials; risk factors for renal cyst development were assessed. Among 17 patients with renal cysts reported as SAEs, evidence of invasion into adjacent structures was noted in seven patients, with no evidence of malignancy found. These patients generally did not require dose reductions, none required permanent crizotinib discontinuation due to this AE, and most continued treatment with clinical benefit. In the blinded IRR, among 255 crizotinib-treated patients, 22%, 3%, and 2% had preexisting simple cysts, complex cysts, or both, respectively. At the 6-month tumor assessment, 9% of all patients had acquired new cysts, and 2% of patients with preexisting cysts had developed new cysts and enlargements (>50%) of preexisting simple cysts. Asians appeared to have an increased risk of developing new cysts on treatment; Koreans in particular had 5.18 times higher odds of developing cysts than non-Asians (95% confidence interval, 1.51–17.78; P = 0.05). Crizotinib treatment appears to be associated with an increased risk of development and progression of renal cysts in patients with ALK-positive NSCLC. While close monitoring is recommended, dosing modification was not generally necessary, allowing patients to remain on crizotinib treatment.

Clinical symptoms and sonographic follow-up after surgical treatment of nonparasitic liver cysts

BackgroundThe optimal treatment of nonparasitic liver cysts is still a topic of debate. Only symptomatic cysts are being considered as requiring treatment. Aim of this study is to evaluate our experience with this disease over the past ten years with a structured follow-up program.MethodsFrom January 2000 to August 2010, 56 consecutive patients with nonparasitic liver cysts were treated at our institution. We assessed morbidity, recurrence and complication rates, quality of life as well as pre- and post-operative sonographic status of the cysts and course of clinical symptoms.ResultsIn 84% of the patients surgery was started as a laparoscopic procedure. Conversion rate was 6.4%. Average diameter of deroofed cysts was 12 cm. Overall complication rate was 16% and overall recurrence rate 28.3% (8.7% recurrences at the surgical site, 19.6% new or enlarged cysts). One half of the patients were symptom-free after surgery and the other half had at least one persisting symptom post-operatively. In one half of these patients with persisting symptoms, symptoms were ameliorated by surgery. In the other half of patients the number of symptoms increased after surgery. Two thirds of the overall patients reported their post-operative health as being good or very good.ConclusionsSurgical deroofing is the most effective treatment option for symptomatic liver cysts. Half of our patient population retained at least one symptom from a group of more than ten abdominal symptoms.Only the minority of these cases may be attributed to true recurrence, de-novo cysts or growing pre-existing cysts. The analysis of our cases suggests that the persistent symptoms in our patients may in part be due to the fact that the association between clinical complaints and the liver cysts was not sufficiently established. A more rigid patient selection should be implemented in order to achieve better results from the treatment of cysts. Because even large cysts are frequently asymptomatic, patient selection should not primarily be based on the cyst size only. The decision should be based strictly on the correlation between cyst / cyst location and symptoms / clinical complaints. In our opinion, further diagnostic procedures may be necessary in individual cases to clarify such a correlation.

Inhibiting the HSP90 chaperone slows cyst growth in a mouse model of autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is a progressive genetic syndrome with an incidence of 1:500 in the population, arising from inherited mutations in the genes for polycystic kidney disease 1 (PKD1) or polycystic kidney disease 2 (PKD2). Typical onset is in middle age, with gradual replacement of renal tissue with thousands of fluid-filled cysts, resulting in end-stage renal disease requiring dialysis or kidney transplantation. There currently are no approved therapies to slow or cure ADPKD. Mutations in the PKD1 and PKD2 genes abnormally activate multiple signaling proteins and pathways regulating cell proliferation, many of which we observe, through network construction, to be regulated by heat shock protein 90 (HSP90). Inhibiting HSP90 with a small molecule, STA-2842, induces the degradation of many ADPKD-relevant HSP90 client proteins in Pkd1(-/-) primary kidney cells and in vivo. Using a conditional Cre-mediated mouse model to inactivate Pkd1 in vivo, we find that weekly administration of STA-2842 over 10 wk significantly reduces initial formation of renal cysts and kidney growth and slows the progression of these phenotypes in mice with preexisting cysts. These improved disease phenotypes are accompanied by improved indicators of kidney function and reduced expression and activity of HSP90 clients and their effectors, with the degree of inhibition correlating with cystic expansion in individual animals. Pharmacokinetic analysis indicates that HSP90 is overexpressed and HSP90 inhibitors are selectively retained in cystic versus normal kidney tissue, analogous to the situation observed in solid tumors. These results provide an initial justification for evaluating HSP90 inhibitors as therapeutic agents for ADPKD.

Substratum preference of Philophthalmus sp. cercariae for cyst formation under natural and experimental conditions.

Selection on parasites should favor adaptations that maximize the probability of transmission to the definitive host, such as the preference for and use of intermediate hosts or encystment substrata that are likely to be consumed by the definitive host. Eye flukes in the genus Philophthalmus are passed to their definitive avian host through the ingestion of metacercariae encysted on hard substrata. The life cycle of these parasites is generally well understood; however, there is almost no information on substratum use or preference of the cercariae of these parasites. In this study, we combine a survey of naturally occurring substrata with experimental, laboratory-based choice tests to determine the preferred substratum of Philophthalmus sp. and whether this preference is affected by the presence and density of pre-existing cysts. A concordance between natural and experimental data show a preference for the shells of multiple species of snail over other hard substrata that are common at the field site, including seaweed, other molluscs, and crustaceans. In addition, we found that cercariae preferred substrata with pre-existing cysts and that this preference seemed to increase with increasing cyst density. Such a preference should lead to an aggregated distribution of cysts among snail shells that may benefit the parasite by increasing the number of potential mates that become established in the definitive host. The identification of a preferred substratum also may help to identify potential definitive hosts that were previously unknown.

Substratum Preference of Philophthalmus sp. Cercariae for Cyst Formation Under Natural and Experimental Conditions

Selection on parasites should favor adaptations that maximize the probability of transmission to the definitive host, such as the preference for and use of intermediate hosts or encystment substrata that are likely to be consumed by the definitive host. Eye flukes in the genus Philophthalmus are passed to their definitive avian host through the ingestion of metacercariae encysted on hard substrata. The life cycle of these parasites is generally well understood; however, there is almost no information on substratum use or preference of the cercariae of these parasites. In this study, we combine a survey of naturally occurring substrata with experimental, laboratory-based choice tests to determine the preferred substratum of Philophthalmus sp. and whether this preference is affected by the presence and density of pre-existing cysts. A concordance between natural and experimental data show a preference for the shells of multiple species of snail over other hard substrata that are common at the field site, including seaweed, other molluscs, and crustaceans. In addition, we found that cercariae preferred substrata with pre-existing cysts and that this preference seemed to increase with increasing cyst density. Such a preference should lead to an aggregated distribution of cysts among snail shells that may benefit the parasite by increasing the number of potential mates that become established in the definitive host. The identification of a preferred substratum also may help to identify potential definitive hosts that were previously unknown.

Development of intratumoral cyst or extratumoral arachnoid cyst in intracranial schwannomas following gamma knife radiosurgery

Intracranial schwannomas presenting with cyst formation following gamma knife radiosurgery (GKRS) were investigated to clarify their clinicopathological characteristics. Between 1994 and 2006, 492 patients presenting with intracranial schwannomas underwent GKRS. Among them, seven cases demonstrated either new formation of cysts or enlargement of preexisting cysts, which were treated with microsurgical intervention. These cases were retrospectively reviewed with regard to neuroradiological findings and histopathology. These seven cases included five vestibular and two trigeminal schwannomas. Preexisting cysts were enlarged following GKRS in three cases, while they were newly formed in four cases. Salvage microsurgery was carried out at 7-167months after the GKRS, and subtotal resection was achieved in three, partial resection with or without cyst fenestration in four. Neurological symptoms were improved in all six symptomatic cases. Preoperative MRI demonstrated two characteristic types of cyst. One was the intratumoral type, indicating hemorrhagic change on the MRI. Histopathological analysis demonstrated a cavernous angioma within the solid compartment of tumor. These two cases demonstrated enlargement of residual tumor with new cyst formation after resection of only the cyst. The other type was extratumoral cyst, which had a structure with a thin cyst wall without contrast enhancement, and the cyst was composed of arachnoid cells without tumor cells. Extratumoral cysts enlarged despite effective control of the tumor itself, which may be caused by osmotic gradient induced by tumor degeneration following GKRS. There were two types of cysts, intratumoral cyst and extratumoral arachnoid cyst, which developed following GKRS in intracranial schwannomas. Resection of the solid compartment as well as the cyst is required in schwannomas with expanding intratumoral cyst. Conversely, fenestration of the cyst alone might be effective in extratumoral arachnoid cysts.

Extensive scrotal calcinosis

Case reportA 46-year-old man was referred to our clinic complainingof nodular lesions located on the scrotum that had graduallyenlarged over a period of 6 years. Due to poor psychosocialand cultural conditions, the patient did not seek medicaladvice until the nodules reached massive dimensions(Figs. 1 and 2). Physical examination revealed multiplenodules on the scrotal skin ranging between 1 to 3 cm indiameter. These were firm and mobile on palpation. Thenodules were only present on the scrotal skin. The patienthad no history of trauma, inflammatory disease or meta-bolic disorders. Urinalysis and blood chemistry tests werewithin normal limits. Subtotal excision of the scrotal wallwas performed. The skin was sutured with 3/0 absorbablesutures in horizontal mattress fashion. The histopathologi-cal examination revealed multiple calcified masses withinthe superficial and mid dermis. Epidermal cyst or eccrinecyst remnants were not observed within or around thelesions. The cosmetic results were excellent. No newlesions were observed during a 6-month follow-up (Fig. 3).DiscussionScrotal calcinosis (SC) was first described by Lewinski in1883 and more than 100 cases have been reported but itspathogenic mechanism is unclear. Clinically, there are hardyellowish nodules that vary in size: from 1 mm to severalcentimetres. Lesions can be solitary or multiple, locatedwithin scrotal skin and can share the characteristics ofepidermoid cysts. Although these nodules are usuallyasymptomatic, they can cause itching [1]. Disease occursusually in middle age and has a slowly growing pattern.Patients attend clinics primarily for aesthetic concerns andsuspicion of malignant disease [2].Whether SC is truly idiopathic or may be the result ofcalcification of preexisting cysts remains a controversialissue. Epidermal or eccrine cyst dystrophic calcificationswere generally accused but cases without any cysticcomponent have been reported. Ito et al. reported a caseof SC originating from eccrine epithelial cysts. This eccrineorigin was discovered via an immunohistochemical studyusing antibodies against carcinoembryonic antigen, epithe-lial membrane antigen and gross cystic disease fluidprotein-15 [3].Song et al. detected epidermal cysts with intact walls in apatient and established the following pathogenic mecha-nism. Cysts are formed, calcification of the intracystickeratinous content occurs with enlargement of the cyst anda subsequent attenuation of the wall. The structure of thecysts becomes indeterminate, along with rupture of theirwalls and the exposure of their contents. This triggers amononuclear cell inflammation or foreign body granulomawith resorption of the cyst walls and of the keratinousmaterial. Finally, only calcified deposits remain [4].Wright et al. conclude that the condition is trulyidiopathic, after failing to show positive staining with

Peritoneal Inclusion Cyst

Hormone changes are thought to influence the etiology and disease process of peritoneal inclusion cysts. The effects of fertility and pregnancy on preexisting cysts are unknown. A 29-year-old woman with recurrent peritoneal inclusion cyst and primary infertility conceived spontaneously after hysterosalpingogram. She presented in the first trimester with rapid, symptomatic enlargement of a 22-cm peritoneal inclusion cyst. Ultrasonogram-guided aspiration was performed. The remainder of her pregnancy and postpartum course were uncomplicated. The presence of a large peritoneal inclusion cyst does not preclude fertility. Pregnancy, a hyperestrogenic state, together with rising human chorionic gonadotropin is a risk for recurrence or enlargement of a preexisting peritoneal inclusion cyst. After conservative management with cystocentesis, there was no further enlargement as pregnancy progressed.

Stage conversion of Toxoplasma gondii in mouse brain during infection and immunodepression.

The kinetics and pattern of expression of bradyzoite-specific proteins were studied in mouse brain during infection with Toxoplasma gondii. Parasites found in the brain 6 days after ingestion of cysts were expressing only tachyzoite-specific proteins (anti-SAG1 antibodies being used as a marker). Bradyzoite-specific protein (Pb36) expression was first found after 9 days in vacuoles containing mixed parasites simultaneously expressing SAG1 and Pb36 or cysts containing parasites expressing only the bradyzoite marker. Reactivation of toxoplasmosis was studied in mouse brain using corticosteroids for immunosuppression. Parasites expressing SAG1 were first found 6 days after the beginning of treatment, but a very heterogeneous pattern was found throughout the study. We simultaneously found vacuoles containing parasites expressing only SAG1 or containing intermediate stages or cysts containing parasites expressing only bradyzoite proteins. A striking observation was the multiplication of cysts in foci, suggesting that the immune suppression triggered the release of parasites from preexisting cysts but that the factors inducing bradyzoite development remained fully effective in driving parasites into this pathway.

Germline Stem Cell Division and Egg Chamber Development in Transplanted Drosophila Germaria

Germline and somatic stem cells reside within the anterior region (or "germarium") of each ovariole in the Drosophila ovary. When individual germaria were dissected free of developing eggs and sheath tissue and transplanted into the abdominal cavity of a host fly, they regenerated ovariole-like structures and continuously supported the entire process of oogenesis, indicating that the stem cells remained functional. This system allowed us to measure the duration of several stages in oogenesis and to analyze the role of specific germarial cells in providing stem cell function. Laser ablation of presumptive germline stem cells near the apical tip prior to transplantation blocked the production of new germline cysts, but allowed previously initiated cysts to complete development. This confirmed the location of germline stem cells and showed that subsequent development of preexisting cysts did not require continued cyst production. Ablation of a distinct group of somatic cells lying close to the germline stem cells ("the terminal filament") increased the rate of oogenesis by approximately 40%, suggesting that the terminal filament may negatively regulate stem cell division.

Epidermoid cyst of the scalp containing human papillomavirus

We report an epidermoid cyst of the scalp with light microscopic and immunohistochemical evidence of human papillomavirus (HPV) infection. Light microscopic features suggesting HPV infection included papillomatosis and hypergranulosis of the cyst lining with the presence of koilocytes. Much of the keratin within the cyst demonstrated parakeratosis. Immunoperoxidase labeling for HPV antigen was noted within koilocytes. Papillomavirus infection has been reported in plantar epidermoid cysts. To our knowledge, this is the first report of a papillomavirus-infected epidermoid cyst in a site other than plantar skin. Light microscopic features of our cases differed from those of the plantar cysts. Epidermoid cysts may be induced by the papillomavirus or the virus may merely infect pre-existing cysts.

Titanium scaphoid implant for scaphoid nonunion

A titanium scaphoid implant was developed in 1985 as an alternative to the silicone model. Surgical indications included aseptic necrosis with arthritic changes of the scaphoid, failures from previous surgery including bone grafting for fracture nonunion, and arthritic involvement of the scaphoid with associated carpal instability, particularly the scapholunate advanced collapse (SLAC) wrist pattern. An additional indication was revision surgery following a previous scaphoid silicone implant with swelling and pain in the presence of cystic or progressive degenerative bony changes. Between 1985 and 1990, Swanson performed 54 titanium scaphoid arthroplasties. The results were analyzed on 28 patients (29 cases) with 24 months follow-up or greater (range 24 to 55 months). Preoperative and postoperative roentgenograms were reviewed to assess changes in carpal height and radiolunate angle. Cystic changes in contiguous carpal bones, bone tolerance, and maintenance of implant position were also evaluated. Postoperatively, there was improved functional use of the hand with marked decreased pain. The carpal height was well maintained and the congruity of the contiguous carpal bones were well maintained. Important steps of the procedure include curettage and cancellous bone grafting of preexisting subchondral bony cysts and correction of associated carpal instability and degenerative changes with selective intercarpal functions