Respiratory System (J00-J99)
- Bronchogenic cysts (congenital lung malformation).
Infectious and parasitic diseases (A00-B99).
- Tuberculosis (consumption).
Circulatory system (I00-I99)
- Lymphangiomas (benign tumors (hamartoma) of the lymphatic vessels).
Mouth, esophagus (esophagus), stomach, and intestines (K00-K67; K90-K93).
Musculoskeletal system and connective tissue (M00-M99).
- Psoas abscess – abscess (collection of pus) in the iliopsoas muscle (pulls from the thoracic/lumbar vertebrae to the ilium/thigh bone).
Neoplasms – tumor diseases (C00-D48).
- Benign (benign) neoplasms
- Fibromatosis
- Lipomas
- Renal tumors such as adenomas, angiomyolipomas
- Neurogenic tumors (schwannoma, neurofibroma), paragangliomas.
- Germ cell tumors (primary tumors are very rare; mostly metastases from testicular tumors).
- Lymphomas (abdominal Hodgkin’s lymphoma: often confined to the spleen and retroperitoneal space).
- Lymph node metastases (e.g., due totesticular, prostate, breast, cervical, endometrial, ovarian, colon, gastric, renal carcinoma).
- Malignant fibrous histiocytoma (dermatofibroma) (elderly patients).
- Malignant mesenchymal tumors (including sarcomas, liposarcomas, leiomyosarcomas).
- Adrenal tumors, unspecified.
- Renal pelvic carcinoma (renal pelvic cancer) and other malignant neoplasms of the kidney, such as sarcomas or lymphomas
- Renal cell carcinoma
- Non-pancreatic pseudocysts (cyst-like structure, which, however, unlike the cyst, has no epithelial lining).
- Wilms tumor (nephroblastoma) – malignant (malignant), embryonal, relatively rare tumor of the kidney; the most common form of renal cell carcinoma (kidney cancer) in childhood; due to the presence of tumor mass, half the abdomen (hemiabdomen) of the patient is often considerably bulging
- Cystadenomas and cystadenocarcinomas.
Genitourinary system (N00-N99)
- Retroperitoneal fibrosis (retroperitoneal fibrosis; synonyms: Albarran-Ormond syndrome, Ormond’s disease, Ormond’s syndrome; Engl. “Gerota’s fascitis” or “Gerota’s syndrome”) slowly increasing fibrosis (connective tissue proliferation) between the posterior peritoneum and the spine with walled-in vessels, nerves and ureters (ureters); autoimmune diseaseSex ratio: males to females: 1: 2; peak incidence: age of 50-60 years, prevalence (disease incidence): 1/200,000.
- Urinomas (pathological accumulation of urine).
Other differential diagnoses
- Pneumoretroperitoneum wg intestinal perforation, necrotizing fasciitis (foudroyant life-threatening infection of the skin, subcutis (subcutaneous tissue) and fascia with progressive gangrene; often involves patients with diabetes mellitus or other diseases leading to circulatory disorders or reduced immune defenses) or pancreatitis (pancreatitis).
- Retroperitoneal fluid collections:
- Hematomas (bruising).
- Lymphoceles
- Urinomas
- Infection
