TaoMedAI/RareMedData huggingface dataset:
Pili torti-onychodysplasia syndrome (ORPHA:2890)
A rare ectodermal dysplasia syndrome characterized by congenital onychodystrophy (particularly of the distal nail) and severe hypotrichosis with alopecia involving the eyebrows, eyelashes and body hair. Scalp, beard, pubic and axillary hair is brittle and shows a twisting pattern on electron microscopy. There have been no further descriptions in the literature since 1991.
Pili torti (ORPHA:2889)
Pili torti is a hair shaft abnormality characterized by flat hair that is twisted at irregular intervals. Hair is normal at birth but progressively stops growing long and becomes fragile. Pili torti can be isolated or occur in association with syndromes such as Menkes disease or Bazex syndrome (see these terms).
Pilocytic astrocytoma (ORPHA:251612)
Pilocytic astrocytoma is a rare subtype of low-grade glioma of the central nervous system characterized by a well circumscribed, often cystic, brain tumor with a discrete mural nodule and long, hair-like projections that extend from the neoplastic astrocytes. Depending on the primary localization and the size of the tumor, patients can present with signs of raised intracranial pressure (headache, vomiting, papilledema), blurred vision, decreased visual acuity, ataxia and/or nystagmus, among others. It is most commonly located in the cerebellum, but ocurrence in the hypothalamus, brain stem, optic chiasma, and hemispheres has also been reported.
Pilodental dysplasia-refractive errors syndrome (ORPHA:2892)
Pilodental dysplasia-refractive errors syndrome is a rare ectodermal dysplasia syndrome characterized by dysplastic abnormalities of the hair and teeth (including hypodontia, abnormally shaped teeth, scalp hypotrichosis and pili annulati), follicular hyperkeratosis on the trunk and limbs, and hyperopia. Intensified delineation, reticular hyperpigmentation of the nape and astigmatism have also been reported. There have been no further descriptions in the literature since 1985.
Pilomatrix carcinoma (ORPHA:499182)
A rare skin tumor characterized by an asymptomatic, solitary, often ulcerated nodule most commonly located in the face, involving the deep dermis, subcutaneous tissue, and skeletal muscle and fascia. Histopathologically, the lesion is composed of aggregates of atypical basaloid cells with numerous mitoses. Typical features include shadow cells, keratin cysts, and trichohyalin and keratohyalin granules. The tumor is locally aggressive and shows a tendency to recur after incomplete excision. Regional lymph node or visceral metastasis has been reported.
Pilomatrixoma (ORPHA:91414)
Pilomatrixoma is a rare and benign hair cell-derived tumor occurring mostly in young adults (usually under the age of 20) and characterized as a 3-30 mm solitary, painless, firm, mobile, deep dermal or subcutaneous tumor, most commonly found in the head, neck or upper extremities. When superficial, the tumors tint the skin blue-red. Multiple pilomatrixomas are seen in myotonic dystrophy, Gardner syndrome, Rubinstein-Taybi syndrome, and Turner syndrome (see these terms).
Pineal parenchymal tumor of intermediate differentiation (ORPHA:251919)
A rare type of pineal parenchymal tumor (PPT) of intermediate-grade malignancy manifesting with visual disturbances, headaches, loss of coordination and balance, nausea and vomiting due to obstructive hydrocephalus, and that is classified as either grade II PPTID (pineal parenchymal tumor of intermediate differentiation) or grade III PPTID according to the degree of neuronal differentiation and mitotic activity.
Pineoblastoma (ORPHA:251909)
Pineoblastoma is a rare, malignant type of supratentorial primitive neuroectodermal tumor (sPNET), found mainly in children (less than 10% of cases are reported in adults), and located in the pineal region of the brain but that can metastasize along the neuroaxis. As it is the most aggressive of the pineal parenchymal tumors, it is usually associated with a poor prognosis.
Pineocytoma (ORPHA:251912)
Pineocytoma is the least aggressive form of pineal parenchymal tumors, manifesting with symptoms such as Parinaud's syndrome (a group of eye movement abnormalities and pupil dysfunction, including deficiency in upward-gaze and convergence-retraction nystagmus), headaches, balance impairment, urinary incontinence, and changes in mood and that are not known to disseminate in a diffuse manner. They are usually associated with a good prognosis.
Pinnae fistula or cyst (ORPHA:155838)
Pinnae fistula or cyst is a rare otorhinolaryngological malformation characterized by the presence of a, usually unilateral, sinus tract or cyst located in the vicinity of the auricle (most frequently identified by a small pit near the anterior margin of the first ascending portion of the helix). Typically, patients are asymptomatic and usually only present symptoms (pain, erythema, discharge from pit) in relation to infection. Renal and inner ear anomalies may be associated.
Pituicytoma (ORPHA:251623)
A rare glial tumor originating from pituicytes, the specialized glial cells of the neurohypophysis, characterized by a sellar or suprasellar mass manifesting with clinical signs secondary to mass effect. Typical manifestations are visual disturbances, headaches, and hypopituitarism. Pituicytomas are low-grade tumors, and prognosis is good after total resection.
Pituitary apoplexy (ORPHA:95613)
A rare pituitary disease characterized by hemorrhagic or non-hemorrhagic necrosis of the pituitary gland. Clinical manifestations typically comprise sudden and severe headache (often with nausea and vomiting), visual disturbances (visual-field defects, loss of visual acuity), oculomotor palsies, and variable degrees of altered consciousness, ranging from lethargy to coma. Acute endocrine dysfunction may also be present, most commonly corticotropic deficiency with severe hypotension and hyponatremia as well as secondary adrenal failure, but also thyrotropic and gonadotropic deficiency.
Pituitary carcinoma (ORPHA:300385)
A rare pituitary tumor characterized by the presence of a pituitary adenoma that has metastasized either within the central nervous system, or to distant sites. The vast majority of pituitary carcinomas are hormonally active, most frequently with ACTH or prolactin production. The most common clinical symptoms are diabetes insipidus, optic nerve dysfunction, anterior pituitary dysfunction, palsy of cranial nerves III, IV, or VI, and headaches, although patients may also be asymptomatic. The tumors behave aggressively, and prognosis is poor.
Pituitary deficiency due to empty sella turcica syndrome (ORPHA:91354)
A rare pituitary deficiency characterized by herniation of the subarachnoid space into the sella turcica, resulting in flattening of the pituitary gland and endocrine dysfunction. Most common endocrine abnormalities are hyperprolactinemia and growth hormone deficit. Clinical symptoms are highly variable and include headaches, irregular menstruation, galactorrhea, obesity, and visual disturbances, among others.
Pituitary deficiency due to Rathke cleft cysts (ORPHA:91350)
A rare, acquired pituitary hormone deficiency characterized by combination of headache, visual field defects that correlate with cyst size, and pituitary dysfunction. Most frequent hormonal manifestations are hypogonadism with amenorrhea/impotence or low libido and galactorrhea.
Pituitary dermoid and epidermoid cysts (ORPHA:91351)
Pituitary dermoid and epidermoid cysts is a rare, acquired pituitary hormone deficiency characterized by the presence of rare, benign tumor in the sellar region. Clinical presentation is either acute or insidious, and is variable according to the cyst location, size and potential rupture. Most commonly patients present with headache, visual disturbances, and pituitary dysfunction.
Pityriasis rubra pilaris (ORPHA:2897)
Pityriasis rubra pilaris is a rare chronic papulosquamous disorder of unknown etiology characterized by small follicular papules, scaly red-orange patches, and palmoplantar hyperkeratosis, which may progress to plaques or erythroderma. Although most of the cases are sporadic and acquired, a familial form of the disease exists.
PLAA-associated neurodevelopmental disorder (ORPHA:521426)
A rare genetic neurological disorder characterized by infantile onset of progressive leukoencephalopathy, microcephaly, severe global developmental delay, and spasticity resulting in quadriparesis and posture deformation. Additional features include an abnormally exaggerated startle reflex, seizures, dystonia, and hypomimia or amimia, as well as progressive chest deformities and contractures of large and hyperextensibility of small joints, among others. Thin corpus callosum is a prominent feature in brain imaging, in addition to white matter abnormalities consistent with leukoencephalopathy.
Placental insufficiency (ORPHA:439167)
A rare obstetric disease characterized by inadequate blood flow to the placenta during pregnancy, resulting in a decrease in trans-placental transfer of oxygen and nutrients to the fetus, potentially leading to fetal growth retardation, distress, or death. Maternal risk factors include preeclampsia, gestational diabetes, and smoking, among others.
Placental site trophoblastic tumor (ORPHA:99928)
A rare gestational trophoblastic neoplasm characterized histologically by invasion of myometrium by intermediate trophoblastic cells without chorionic villi and containing human placental lactogen hormone (hPL). Tissue necrosis is usually absent and hemorrhage is mild. The tumor develops from the placental implantation site and always occurs following pregnancy, voluntary termination of pregnancy (VTP) or miscarriage. Indicative signs are irregular metrorrhagia some time after spontaneous miscarriage or VTP, presence of metastasis or unexplained metrorrhagia in the weeks and months following normal childbirth or ectopic pregnancy.
Plague (ORPHA:707)
Plague is a severe bacterial infection caused by the Gram-negative bacterium Yersinia pestis.
Epidemiology
It is extremely rare in Europe but still spreads in Africa and, to a lesser degree, in Asia and Latin America.
Clinical description
There are two clinical forms of the disease: bubonic plague, characterized by painfully inflamed lymph nodes called "buboes'', an elevated temperature and an altered clinical state; and pulmonary plague which manifests itself as thoracic pain, a cough with bloody expectoration, an elevated temperature, an altered clinical state and consciousness disorders.
Etiology
Plague is transmitted from animals to humans by fleas. Rodents are the reservoir for the disease. Plague is also transmitted between humans via the respiratory route.
Diagnostic methods
Diagnosis is based on isolation of the bacterium in the bubo, blood or expectoration, or from serology.
Management and treatment
Many classes of antibiotics are effective against Yersinia pestis (aminoglycosides, tetracyclines, cotrimoxazole, rifampicin, fluoroquinolones etc.).
Prognosis
Without treatment, the course of the disease is rapidly fatal.

                            Last update: 
                            November 2009


                            - Expert reviewer(s): 
                            Dr F RACHILLAS
Plasma cell leukemia (ORPHA:454714)
A rare plasma cell neoplasm characterized by peripheral plasmacytosis, usually with extensive and diffuse infiltration of the bone marrow, and monoclonal paraproteinemia. Neoplastic plasma cells may also be found in extramedullary sites, such as the liver or spleen, among others. Most cases present as primary plasma cell leukemia without previous diagnosis of myeloma. The condition can also represent leukemic transformation of plasma cell myeloma (secondary plasma cell leukemia). Clinical manifestations include lymphadenopathy, organomegaly, renal failure, bone marrow failure, and peripheral neuropathies. High serum levels of lactate dehydrogenase and beta2-microglobulin, as well as hypercalcemia (potentially leading to hypercalcemic crisis) are typically observed.
Plasmablastic lymphoma (ORPHA:289666)
A rare aggressive B-cell non-Hodgkin lymphoma characterized by neoplastic cells resembling B immunoblasts or plasmablasts with a CD20-negative plasmacytic phenotype. The tumor may occur in the oral cavity, the gastrointestinal tract, or other, predominantly extranodal, sites and is typically associated with immunodeficiency or -suppression. The tumor cells are EBV-positive in most cases. Patients often present with disseminated bone involvement. Paraproteinemia may also be detected. Prognosis is generally poor.
Plasmacytoma (ORPHA:86855)
Plasmacytoma is a localized mass of neoplastic monoclonal plasma cells that represents approximately 5% of all plasma cell neoplasms. There are two separate entities: primary plasmacytoma of the bone and extramedullary plasmacytoma of the soft tissues. Of the extramedullary plasmacytomas, 80% occur in the head and neck, usually in the upper respiratory tract. The median age at diagnosis is 50 years and the male to female ratio is 3:1. Long-term survival is possible following local radiotherapy, particularly for soft tissue presentations.
Platyspondylic dysplasia, Torrance type (ORPHA:85166)
Platyspondylic lethal skeletal dysplasia (PLSD), Torrance type (PLSD-T) is a skeletal dysplasia characterised by severe limb shortening (short and broad long bones), platyspondyly with wafer-like vertebral bodies, short ribs with anterior cupping, severe hypoplasia of the lower ilia and radial bowing. Histological findings include slightly enlarged chondrocytes and hypercellularity. The prevalence is unknown. The disorder is transmitted as an autosomal dominant trait and is caused by mutations in the C-propeptide domain of the COL2A1 gene. Although PLSD-T is generally lethal, survival to adulthood has been reported in two families.
PLCG2-associated antibody deficiency and immune dysregulation (ORPHA:300359)
A rare, hereditary, immune deficiency with skin involvement characterized by early-onset cold urticaria after generalized exposure to cold air or evaporative cooling and not after contact with cold objects. Additional immunologic abnormalities are often present - antibody deficiency, recurrent infections, autoimmune disease and symptomatic allergic disease.
PLEC-related intermediate epidermolysis bullosa simplex without extracutaneous involvement (ORPHA:79401)
A rare, inherited, epidermolysis bullosa simplex characterized by primarily acral blistering with onset typically at birth. Patients have easy bruisability, hemorrhagic blistering, and onychogryphosis.
Plectin-related limb-girdle muscular dystrophy R17 (ORPHA:254361)
A form of limb-girdle muscular dystrophy characterized by proximal muscle weakness presenting in early childhood (with occasional falls and difficulties in climbing stairs) and a progressive course resulting in loss of ambulation in early adulthood. Muscle atrophy and multiple contractures have also been reported in rare cases.
Pleomorphic liposarcoma (ORPHA:99969)
Pleomorphic liposarcoma (PLS), the rarest subtype of liposarcoma (LS; see this term), is an aggressive, fast growing tumor located usually in the deep soft tissues of the lower and upper extremities. It is characterized by a variable number of pleomorphic lipoblasts and, in contrast to dedifferentiated liposarcoma, it lacks any association with well-differentiated liposarcoma (see these terms).
Epidemiology
The incidence is approximately 1/2,000,000 per year and it accounts for 5-10% of all LS cases.
Clinical description
PLS usually presents in older individuals with a typical age at diagnosis of 50-70 years. PLS is most commonly a firm, rapidly growing mass in the deep compartments of the lower and upper extremities but can also be located in the abdomen or chest wall in rare cases. PLS has a high (>50%) risk of metastasis, primarily to the lungs. Metastasis is rapid, often leading to death.
Etiology
The etiology is unknown. PLS is characterized by highly complex chromosome alterations, including polyploidy and various chromosomal duplications, deletions and complex rearrangements.
Diagnostic methods
When a mass is detected, computed tomography (CT) or magnetic resonance imaging (MRI) is performed. Chest and abdominal lesions do not require pretreatment biopsy unless resection is likely to be incomplete or highly morbid. Extremity lesions are generally sampled by multiple core biopsies to make the histological diagnosis of PLS. Histologically PLS contains a variable number of pleomorphic lipoblasts, with hemorrhage and necrosis commonly observed.
Differential diagnosis
PLS can often be mistaken for myxofibrosarcoma or pleomorphic undifferentiated sarcoma (see these terms).
Management and treatment
Treatment involves the surgical excision of the tumor and surrounding normal tissue. In rare cases amputation of the limb is necessary. Tumors that are large (>5-8 cm) or marginally resectable may be treated with preoperative chemotherapy. Adjuvant radiation is recommended if the surgical margin is narrow or positive for sarcoma. Lifelong follow-up is recommended in order to monitor for recurrence at the initial site as well as distant metastasis.
Prognosis
PLS has the poorest prognosis of all the LS subtypes. Five-year survival is 59%.

                            Last update: 
                            January 2013


                            - Expert reviewer(s): 
                            Dr Samuel SINGER
Pleomorphic rhabdomyosarcoma (ORPHA:293199)
A rare soft tissue sarcoma characterized by a high-grade lesion occurring almost exclusively in adults, composed of bizarre polygonal, round, and spindle cells with evidence of skeletal muscle differentiation. Patients usually present with a rapidly growing, painful mass located in the deep soft tissues of the extremities, but also other anatomic regions. Prognosis is generally poor.
Pleomorphic salivary gland adenoma (ORPHA:454821)
A rare tumor of salivary glands characterized by a benign, well-circumscribed, slow-growing, painless mass most commonly occurring in the parotid gland (but also the palate, submandibular gland, or nasal septal mucosa), histopathologically composed of epithelial and myoepithelial / stromal components. Possible signs and symptoms depend on the location of the tumor and include facial nerve weakness, mild dysphagia, or unilateral nasal obstruction. Recurrence rates are low, although tumor rupture and spillage have been reported. Malignant transformation may occur in a small percentage of cases.
Pleomorphic xanthoastrocytoma (ORPHA:251607)
A rare low-grade astrocytoma characterized by superficial location in the cerebral hemispheres with involvement of the meninges, composed of GFAP-expressing cells showing nuclear and cytoplasmic pleomorphism and xanthomatous change, surrounded by a reticulin network. The tumor corresponds to WHO grade II and typically affects children and young adults, who often present with a long history of seizures. Extent of resection and mitotic index are important prognostic factors.
Pleural empyema (ORPHA:449266)
A rare pulmonary condition characterized by accumulation of pus in the pleural cavity, most commonly as a consequence of pneumonia, but also trauma and surgical procedures. Clinical signs and symptoms depend on host factors, as well as the nature of the causative microorganism, among others, and include cough, chest pain, dyspnea, and fever.
Pleural mesothelioma (ORPHA:50251)
Malignant mesothelioma is a fatal asbestos-associated malignancy arising in the lining cells (mesothelium) of the pleural and peritoneal cavities, as well as in the pericardium and the tunica vaginalis.
Epidemiology
The exact prevalence is unknown but it is estimated that mesotheliomas represent less than 1% of all cancers. Its incidence is increasing, with an expected peak in the next 10-20 years.
Clinical description
Pleural malignant mesothelioma is the most common form of mesothelioma. Typical presenting features are chest pain and dyspnea. Breathlessness due to a pleural effusion without chest pain is reported in about 30% of patients. A chest wall mass, weight loss, sweating, abdominal pain and ascites (due to peritoneal involvement) are less common presentations.
Etiology
Mesothelioma is directly attributable to occupational asbestos exposure with a history of exposure in over 90% of cases. There is also evidence that mesothelioma may result from both para-occupational exposure and non-occupational 'environmental' exposure. Idiopathic or spontaneous mesothelioma can also occur in the absence of any exposure to asbestos, with a spontaneous rate in humans of around one per million.
Diagnostic methods
A combination of accurate exposure history, along with examination radiology and pathology are essential to make the diagnosis. The most suggestive CT findings indicating malignant pleural disease are 1) a circumferential pleural rind, 2) nodular pleural thickening, 3) pleural thickening of >1cm and 4) mediastinal pleural involvement.
Differential diagnosis
Distinguishing malignant from benign pleural disease can be challenging.
Management and treatment
Involvement of a multidisciplinary team is recommended to ensure prompt and appropriate management, using a framework of radiotherapy, chemotherapy, surgery and symptom palliation with terminal care. Compensation issues must also be considered.
Prognosis
Life expectancy in malignant mesothelioma is poor, with a median survival of about one year following diagnosis.

                            Last update: 
                            December 2008


                            - Expert reviewer(s): 
                            Pr John MOORE  - Dr Robert PARKER  - Pr John WIGGINS
Pleuro-pericardial cyst (ORPHA:99131)
Pleuro-pericardial cyst is a rare, mostly congenital, pericardium anomaly characterized by the presence of, usually asymptomatic, cysts which are typically located in the right costophrenic angle and are usually incidentally diagnosed. On occasion, it manifests with chest pain, dyspnea, tachycardia, persistent cough or cardiac arrhythmias. The condition is usually benign, but rare complications, such as cardiac tamponade, cardiogenic shock, mitral valve prolapse, hoarseness atrial fibrillation, right ventricular outflow, tract obstruction, spontaneous internal hemorrhage, pulmonary stenosis and sudden death, may occur.
Pleuropulmonary blastoma (ORPHA:64742)
A rare respiratory tumor characterized by an aggressive, malignant, dysontogenetic neoplasm of intrathoracic (pulmonary, pleural, or combined) mesenchyme occurring in young children. Three subtypes can be distinguished, type 1 being purely cystic, type 2 cystic and solid, and type 3 purely solid. Type 1 lesions may progress to the more malignant types 2 and 3, which are associated with central nervous system and bone metastasis. The tumor is often part of pleuropulmonary blastoma family tumor and dysplasia syndrome. It can also be associated with multilocular cystic nephroma or other neoplasms. Patients usually present with dyspnea or other respiratory problems, and sometimes pneumothorax.
PLIN1-related familial partial lipodystrophy (ORPHA:280356)
A rare genetic lipodystrophy characterized by loss of subcutaneous adipose tissue primarily affecting the lower limbs and gluteal region due to a defect in the PLIN1 gene. Associated features of insulin resistance, hepatic steatosis, dyslipidemia, hypertension, axillary acanthosis nigricans and muscular hypertrophy of the lower limbs are typical.