Human health and medicine

Persistent atrial fibrillation

Persistent atrial fibrillation (PersAF, persistent AFib) is continuous atrial fibrillation lasting more than 7 days and requiring intervention, distinct from paroxysmal (12 months) forms; higher stroke and mortality risk than paroxysmal AF, treated with anticoagulation, rate/rhythm control, and increasingly first-line ablation.

Persistent cloaca

Persistent cloaca (cloacal malformation, ICD-11 LB17.2) is a rare congenital anomaly in girls where urethra, vagina, and rectum drain through one common perineal channel; incidence about 1 in 50,000, treated by staged reconstructive surgery.

Persistent eustachian valve

Persistent eustachian valve (ORPHA:99120, ICD-10 Q26.8): rare congenital IVC anomaly with postnatal persistence of the eustachian valve remnant; often asymptomatic, but can cause IVC obstruction, thrombosis, endocarditis, or right-to-left shunt with patent foramen ovale.

Persistent fetal circulation

Persistent fetal circulation, also called persistent pulmonary hypertension of the newborn (PPHN), is failure of fetal-to-neonatal circulatory transition causing right-to-left shunting, cyanosis, and refractory hypoxemia in about 1–2 per 1,000 live births.

Persistent fifth aortic arch

Persistent fifth aortic arch (PFAA), double-lumen aortic arch: rare congenital anomaly from failure of the fifth embryonic arch to regress; Weinberg types A to C; associated with coarctation, interrupted arch, VSD, pulmonary atresia.

Persistent genital arousal disorder

Persistent genital arousal disorder (PGAD), also called genito-pelvic dysesthesia, is a distressing condition of unwanted genital arousal without sexual desire, first described in 2001, with prevalence estimates of 0.6–3% and neuropathic, pelvic floor, and medication-related causes.

Persistent hyperinsulinaemic hypoglycaemia of infancy

Persistent hyperinsulinaemic hypoglycaemia of infancy (PHHI), now called congenital hyperinsulinism, is a genetic disorder of dysregulated pancreatic beta-cell insulin secretion causing severe infant hypoglycaemia, most often from ABCC8 or KCNJ11 KATP-channel mutations.

Persistent hyperplastic primary vitreous

Persistent hyperplastic primary vitreous (PHPV), now called persistent fetal vasculature (PFV), is a congenital eye malformation from failed hyaloid vessel regression, usually unilateral, causing infantile leukocoria, microphthalmia, and cataract, and mimicking retinoblastoma.

Persistent idiopathic facial pain

Persistent idiopathic facial pain (PIFP), formerly atypical facial pain, is a rare chronic facial pain recurring daily over 3 months without neurological deficit or identifiable cause, treated conservatively with antidepressants.

Persistent Müllerian duct syndrome

Persistent Müllerian duct syndrome (PMDS), also called persistent Müllerian derivatives, is a rare autosomal recessive 46,XY difference of sex development in which AMH or AMHR2 mutations leave a uterus and fallopian tubes in otherwise normally virilized males, presenting as cryptorchidism or inguinal hernia.

Persistent placoid maculopathy

Persistent placoid maculopathy (PPM) is a rare idiopathic bilateral chorioretinopathy with well-defined white plaque-like macular lesions, first described in 2007, most often affecting Caucasian men in their 50s and 60s.

Persistent polyclonal B-cell lymphocytosis

Persistent polyclonal B-cell lymphocytosis (PPBL), also called B-cell lymphocytosis with binucleated lymphocytes, is a rare benign hematological disorder of middle-aged female smokers with polyclonal B-cell lymphocytosis, binucleated lymphocytes, raised polyclonal IgM, HLA-DR7 association, and +i(3q), distinct from CLL and monoclonal B-cell lymphocytosis.

Persistent Postural-Perceptual Dizziness

Persistent postural-perceptual dizziness (PPPD), also called chronic subjective dizziness or phobic postural vertigo, is a chronic functional vestibular disorder defined by Bárány Society 2017 criteria: persistent non-spinning dizziness on most days for 3+ months, worsened by upright posture, motion, and visual stimuli; ICD-11 code AB32.0.

Persistent pupillary membranes

Persistent pupillary membrane (PPM), remnants of the fetal tunica vasculosa lentis, appears as iris strands crossing the pupil; seen in about 95% of neonates and 20% of adults, usually asymptomatic, treated only if vision-threatening.

Persistent truncus arteriosus

Persistent truncus arteriosus, also called common arterial trunk, is a rare congenital heart defect with one arterial trunk and truncal valve, always with a VSD; neonatal repair is required, with frequent later conduit and valve reinterventions.

Persistent vegetative state

Persistent vegetative state (PVS), also called unresponsive wakefulness syndrome, is complete unawareness with sleep-wake cycles after brain injury lasting over 1 month; misdiagnosis reaches 37–43% and some patients recover consciousness.

Person-centered therapy

Person-centered therapy, also called client-centered or Rogerian therapy, is a non-directive psychotherapy developed by American psychologist Carl Rogers in the 1940s, built on empathy, congruence, and unconditional positive regard.

Personal protective equipment

Personal protective equipment (PPE): worn or held gear, from N95/FFP2 respirators to gloves and eye protection, regulated by OSHA/NIOSH in the US and EU Regulation 2016/425; last tier of the hierarchy of controls.

Personal trainer

Personal trainer: certified fitness professional designing individualized exercise programs. Also exercise trainer, CPT. US median pay $47,160 (May 2025); 388,400 jobs; 7% growth 2025-2035; NCCA accreditation is the hiring benchmark.

Personality disorder

Personality disorder, also called personality pathology, is a mental disorder of rigid, maladaptive patterns of thinking, relating, and impulse control. ICD-11 (2022) replaced categories with severity levels plus five trait domains; DSM-5 keeps categories and an alternative dimensional model.

Oct 22, 2026

Personalized protein corona

The personalized protein corona (PPC) is the patient-specific layer of proteins that forms on a nanoparticle in blood plasma, giving the same particle different biological behavior in each patient.

Personnel Selection

Personnel selection: the formal process of assessing job applicants against job requirements to hire the most qualified candidate. Structured interviews top the 2022 validity rankings (.42); combining methods raises validity further.

Perspiration

Perspiration (sweating): secretion of fluid by eccrine and apocrine sweat glands for evaporative cooling; up to 4 L/hour; sweat chloride test diagnoses cystic fibrosis; hyperhidrosis is excessive sweating.

PERT trial

PERT trial (NCT03663543), Intravenous Estrogen in Kidney Transplant Study: University of Pennsylvania phase 1/2 randomized placebo-controlled trial of peri-operative IV conjugated estrogen to reduce ischemia reperfusion injury and delayed graft function in female deceased donor kidney transplant recipients.

Pertuzumab

Pertuzumab (Perjeta, formerly 2C4/Omnitarg) is a humanized monoclonal antibody, the first HER2 dimerization inhibitor, approved in 2012 with trastuzumab and docetaxel for HER2-positive metastatic breast cancer, later adjuvant and neoadjuvant.

Sep 29, 2026

Pertuzumab/trastuzumab regimen

The pertuzumab/trastuzumab regimen is a dual HER2-targeted antibody combination, usually given with chemotherapy or endocrine therapy, used to treat HER2-positive breast cancer in metastatic, neoadjuvant, and adjuvant settings, first FDA-approved in 2012.

Pervasive developmental disorder not otherwise specified

PDD-NOS (pervasive developmental disorder not otherwise specified, atypical autism) was a DSM-IV residual autism-spectrum diagnosis for autistic-like social-communication impairment not meeting full autism criteria; DSM-5 (2013) and ICD-11 merged it into autism spectrum disorder.

Pervasive developmental disorders

Pervasive developmental disorders (PDD), also called autism spectrum disorders, were the ICD-10/DSM-IV category of five childhood-onset conditions (autistic disorder, Asperger's, PDD-NOS, Rett's, CDD) merged into autism spectrum disorder by DSM-5 in 2013.

Perverted nystagmus

Perverted nystagmus, now termed cross-coupled nystagmus by the Barany Society, is nystagmus arising in a plane different from the stimulus, classically vertical or rotatory caloric nystagmus, usually indicating central vestibular or cerebellar pathology though it can be a normal variant.