Guidelines for Diagnosis of the Lynch Syndrome

The Lynch syndrome is the most common inherited syndrome associated with colorectal cancer, accounting for 3% of new diagnoses; it is also associated with extracolonic cancers, the most common of which is endometrial cancer.
The Lynch syndrome phenotype includes a propensity for cancers of the proximal colon, poor tumor differentiation with mucinous or signet-ring cell histologic features or a medullary growth pattern, abundant infiltrating lymphocytes in the tumor, and synchronous and metachronous colorectal cancers. Continue reading

Diagnostic Criteria for Primary Myelofibrosis (PMF)

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm (MPN) characterized by stem cell-derived clonal myeloproliferation that is often but not always accompanied by JAK2, CALR or MPL mutation, abnormal cytokine expression, bone marrow fibrosis, anemia, splenomegaly, extramedullary hematopoiesis (EMH), constitutional symptoms, cachexia, leukemic progression and shortened survival. Continue reading

Diagnostic Criteria for Essential Thrombocytosis (ET)

Essential Thrombocytosis (ET) is the only chronic myeloproliferative disorder (MPD) without a specific phenotype. Because isolated thrombocytosis can be the initial clinical manifestation of polycythemia vera (PV), primary myelofibrosis (PMF), or chronic myelogenous leukemia, ET is not only a diagnosis of exclusion, it should also not be considered a single disease entity. Continue reading

New Diagnostic Criteria for Common Variable Immune Deficiency (CVID)

Common variable immunodeficiency disorders (CVIDs) are the most frequent symptomatic primary immune deficiency condition in adults. The genetic basis for the condition is not known and no single clinical feature or laboratory test can establish the diagnosis; it has been a diagnosis of exclusion. In areas of uncertainty, diagnostic criteria can provide valuable clinical information. Continue reading

Diagnostic Criteria of Hemophagocytic Lymphohistiocytosis (HLH)

Hemophagocytic lymphohistiocytosis (HLH) is a frequently fatal and likely underdiagnosed disease involving a final common pathway of hypercytokinemia, which can result in end-organ damage and death.
Although an early diagnosis is crucial to decrease mortality, the definitive diagnosis is often challenging because of the lack of specificity of currently accepted diagnostic criteria and the absence of confirmatory gold standards. Continue reading

Diagnostic Criteria of Langerhans Cell Histiocytosis (LCH)

The diagnosis of Langerhans Cell Histiocytosis (LCH) is based on histological and immunophenotypic examination of lesional tissue. The main feature is the morphologic identification of the characteristic LCH cells. Additionally, positive staining of the lesional cells with CD1a and/or Langerin (CD207) is required for definitive diagnosis. Continue reading

Diagnosis of Diabetes Insipidus (DI)

Diabetes insipidus is a disease in which large volumes of dilute urine (polyuria) are excreted due to vasopressin (AVP) deficiency [central diabetes insipidus (CDI)], AVP resistance [nephrogenic diabetes insipidus (NDI)], or excessive water intake (primary polydipsia). Polyuria is characterized by a urine volume in excess of 2 l/m2/24 h or approximately 150 ml/kg/24 h at birth, 100–110 ml/kg/24 h until the age of 2 years and 40–50 ml/kg/24 h in the older child and adult. Continue reading

Diagnostic Criteria for Catastrophic Antiphospholipid Syndrome (CAPS)

The Catastrophic Antiphospholipid Syndrome (CAPS) is a rare life-threatening form of Antiphospholipid Syndrome (APS) in which widespread intravascular thrombosis results in multiorgan ischemia and failure. CAPS is the initial presentation of APS in nearly half of patients, while the remaining half has a history of APS. Continue reading