Subcutaneous fat necrosis of the newborn: A systematic review of surgical management and outcomes.

BACKGROUND: Subcutaneous fat necrosis of the newborn (SCFN) is a rare form of panniculitis manifesting as erythematous plaques or nodules at sites of brown fat in neonates. Surgical management may be indicated in severe cases; however, there is a paucity of literature compiling presentations and outcomes of these surgical patients. METHODS: The authors performed a systematic review, in consultation with a licensed librarian, on MEDLINE and Embase for studies including patients with SCFN who were surgically managed. RESULTS: The search strategy generated 705 results, among which 213 (30.2%) were excluded for lack of discussion on surgical management. Twenty-two studies discussed surgical management of SCFN in 26 patients, but in 6 of these studies the patients were not surgically managed. Ultimately, 16 articles with 16 patients who were surgically managed were included in the study. Average age at diagnosis was 11.8 ± 9.8 days; average age at surgery was 39.5 ± 70.4 days. The most common etiologies were "unknown" (6, 37.5%), therapeutic hypothermia (4, 25.0%), and birth complications (4, 25.0%). Patients harbored nodules on the back (14, 87.5%), upper extremities (7, 43.8%), lower extremities (7, 43.8%), buttocks (5, 31.3%), and head or neck (3, 18.8%). Linear regression models revealed the presence of back lesions and predicted concomitant medical complications (ß = 2.71, p = 0.021). CONCLUSIONS: Patients undergoing surgical management for SCFN most commonly harbor lesions on the back and extremities that are secondary to therapeutic hypothermia or of unknown origin. Reporting of additional cases is needed to further elucidate surgical management and outcomes.

Fat necrosis in the breast: a multimodality imaging review of its natural course with different aetiologies.

Fat necrosis of the breast is a commonly encountered condition in daily practice. It is a benign pathology, but it can have variable manifestations and patterns that may sometimes mimic malignancy, depending on its stage of evolution and its underlying cause. This review demonstrates the wide spectrum of appearances of fat necrosis on mammography, digital breast tomosynthesis (DBT), ultrasound, magnetic resonance imaging (MRI), computed tomography (CT), and positron-emission tomography (PET). Sequential follow-up images are included in some cases to illustrate the temporal change of the findings. The typical location and distribution of fat necrosis from a comprehensive list of aetiologies are discussed. Improved knowledge of the multimodality imaging features of fat necrosis could enhance diagnostic accuracy and clinical management, thus avoiding unnecessary invasive investigations.

Acute and Chronic Alcoholic Pancreatitis, Including Paraduodenal Pancreatitis.

CONTEXT.­: In the last 2 decades there has been significant progress in typing and recognition of pancreatitis, a necroinflammatory and fibroinflammatory process of multifactorial origin. OBJECTIVE.­: To present the current state of pathology and pathogenesis of alcohol-associated pancreatitis, including paraduodenal pancreatitis. In the context of the most important epidemiologic, clinical, and radiologic features, the related macroscopic changes and histopathologic characteristics are addressed. DATA SOURCES.­: In acute pancreatitis we discuss the pathologic findings that distinguish mild from severe pancreatitis and highlight autodigestive fat necrosis as the initial morphologic damage. In chronic pancreatitis we present a histologic staging system that describes the damage patterns as a necrosis-fibrosis sequence that takes place during the development of early to advanced and end-stage chronic pancreatitis. In paraduodenal pancreatitis the anatomic peculiarities are related to the sequence of morphologic changes that are correlated to the most important imaging findings. Pathogenetically, we discuss the role of alcohol overconsumption in triggering autodigestive fat necrosis in the pancreas, the repair of which results in a pancreas-transforming fibroinflammatory process. CONCLUSIONS­: Whereas in acute pancreatitis there are no lesions that are diagnostic for alcohol overconsumption and that exclude other etiologies such as gallstone disease or drugs, the sequence of damage patterns in chronic pancreatitis are strongly related to the effect of alcohol overconsumption and allow in many cases the distinction from hereditary, autoimmune, or obstructive pancreatitis. Paraduodenal pancreatitis can be considered a special manifestation of alcoholic pancreatitis.

Rapid cytologic diagnosis of subcutaneous fat necrosis of the newborn.

Subcutaneous fat necrosis of the newborn is a rare self-limited panniculitis that classically presents within the first few weeks of life. The diagnosis is typically clinical, but some cases require skin biopsy with hematoxylin and eosin stain for confirmation. We report a previously undocumented rapid diagnostic protocol that involves collecting a small amount of exudate from a suppurative lesion, placement onto a slide without fixation, and simply viewing the material under a microscope. This novel and practical method of diagnosis reveals doubly refractile crystals diagnostic of subcutaneous fat necrosis without a biopsy, which may be helpful for rapid diagnosis or use in low resource settings.

A woman with recurrent umbilical bleeding: a case report.

BACKGROUND: Umbilical discharge in an adult is rare and generates broad diagnostic considerations. Umbilical anatomy is variable owing to congenital abnormalities and acquired pathology such as umbilical hernias. The umbilicus can be a site of primary or metastatic malignancy or endometriosis. CASE PRESENTATION: A 40-year-old white American woman came to the clinic with a 2-day history of spontaneous umbilical bleeding. She reported periumbilical pain associated with nausea and emesis. There were no visible skin abnormalities, but deep palpation of the abdomen produced a thin, watery, serosanguineous fluid from the umbilicus. She experienced a similar episode of umbilical bleeding 5 years prior without clear cause. Laboratory workup was notable for mildly elevated C-reactive protein . Computed tomography imaging revealed a fat-containing umbilical hernia with fat necrosis, necessitating complete surgical resection of the umbilicus. CONCLUSIONS: Umbilical hernia with fat necrosis is a rare condition that should be considered in adults with umbilical discharge. Additional diagnostic considerations in adults with spontaneous umbilical bleeding/discharge include embryonal remnants, omphalitis, and metastasis. If the cause is not readily apparent on physical exam, imaging with computed tomography should be considered to assess for hernia and embryonal anomalies.

Right Epipericardial Fat Necrosis After Thymectomy.

A 62-year-old male patient underwent median sternotomy and thymectomy for thymoma (World Health Organization classification type B1+B3, Masaoka classification stage II). A 10-month follow-up postoperative computed tomography showed a 22-mm nodule in the anterior mediastinal lipid tissue just above the right diaphragm. The patient was followed for 8 years, and the nodule's capsule eventually became calcified. Considering the possibility of postoperative recurrence of thymoma, we excised the nodule. The pathologic diagnosis was epipericardial fat necrosis. In some cases, fat necrosis is difficult to distinguish from malignancy by imaging only; surgical resection has diagnostic significance and should be considered.

The Influence of Closing the Abdominal Donor-Site Superficial Fascial System in Deep Inferior Epigastric Perforator Flap Breast Reconstruction.

BACKGROUND: The superficial fascial system is routinely closed to alleviate tension at the abdominal donor site after harvest of the deep inferior epigastric artery perforator flap (DIEP) for breast reconstruction. This is thought to decrease rates of wound dehiscence and improve contour postoperatively. There has been no comparative analysis on closure of the superficial fascial system and its effect on donor-site outcomes. METHODS: The authors retrospectively evaluated outcomes of DIEP flap breast reconstructions performed between 2017 and 2019. After May of 2018, the surgeons collectively agreed to stop closure of the superficial fascial system. All subsequent patients underwent closure of rectus abdominis fascia followed by skin closure. Patient demographic data and abdominal donor-site comorbidities were recorded between the superficial fascial system closure and no-superficial fascial system closure groups. Representative photographs of patients from the two groups were blindly assessed for scar appearance and contour using previously published grading scales. The results were compared. RESULTS: DIEP flap breast reconstruction was performed in 103 consecutive women. Among patients with abdominal donor-site reconstruction, 66 had superficial fascial system closure and 37 did not. There was not a significant difference in fat necrosis or wound dehiscence between the two groups (p = 0.29 and p = 0.39, respectively). Postoperative abdominal scar and contour were evaluated by 10 independent raters and showed no significant difference between the two groups. CONCLUSION: Omission of superficial fascial system closure resulted in no difference in wound dehiscence or fat necrosis rates and aesthetic appearance of the abdominal scar and contour. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Atypical facial presentation of subcutaneous fat necrosis of the newborn.

Subcutaneous fat necrosis of the newborn (SCFN) is a rare self-limiting panniculitis. It is thought to be associated with perinatal hypoxia and therapeutic hypothermia. It is characterised by firm subcutaneous nodules on the back, shoulder and arms. We present a rare facial presentation of SCFN in a 4-week-old infant with no history of therapeutic cooling. She presented with a discrete right cheek mass with no overlying skin changes. We present the diagnostic challenge and undertake a review of the literature. SCFN is an important differential diagnosis in a neonate with subcutaneous facial lesions. SCFN can be complicated by metabolic derangements including hypercalcaemia.

Natural course of fat necrosis after breast reconstruction: a 10-year follow-up study.

BACKGROUND: Although fat necrosis is a minor postoperative complication after breast reconstruction, occasionally it mimics to tumor recurrence in patients with breast cancer. Therefore, the surgeon should distinguish between benign fat necrosis and true local recurrence. The authors evaluated the clinical characteristics of fat necrosis after breast reconstruction and investigated the natural course of fat necrosis. METHODS: Between 2007 and 2013, a total of 362 patients underwent breast reconstruction after partial or total mastectomy for breast cancer in Kyungpook National University Hospital. Clinicopathologic characteristics and the occurrence of fat necrosis were assessed during surveillance for 10 years of mean follow-up period. RESULTS: There were 42 cases (11.6%) of fat necrosis after breast reconstruction with partial or total mastectomy which were confirmed by needle or excision biopsy. The fat necrosis was resolved after a mean period of 45.9 months (SD, ± 42.1) and 26 cases (61.9%) of fat necrosis were almost completely resolved (less than 5 mm) during 10-year follow-up period. CONCLUSION: Based on the natural course of fat necrosis, the fat necrosis after breast reconstruction can be only monitored, if pathologic confirmation was done. More than half of the cases will be resolved within 2-3 years.

Sonography of Encapsulated Fat Necrosis with Histologic Correlation.

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Fat necrosis of the newborn. / Necrosis grasa del recién nacido.

INTRODUCTION: Panniculitis is a group of diseases that affect subcutaneous fat tissue and clinically manifest as nodules. Its pathogenesis is not entirely clear, and it is usually asymptomatic. The confirma tory diagnosis is histological. OBJECTIVE: To describe the clinical and histopathological characteristics of a case of fat necrosis, a specific form of panniculitis in the newborn (NB). CLINICAL CASE: 40-week female NB, born by emergency cesarean section due to fetal tachycardia with meconium, Apgar score 7-8-9. She required oxygen and positive pressure for five minutes. On the fifth day of life, she presen ted an increased volume in the posterior trunk region, with an erythematous - purplish discoloration, which is soft and non-tender to palpation. Skin and soft tissues ultrasound showed increased echo genicity of the subcutaneous cellular tissue and loss of definition of the adipocytes of 42.3 x 9.7 x 20.1 mm approximately, without vascularization. Skin biopsy showed epidermis with irregular acanthosis and basket-weave orthokeratosis; papillary dermis with inflammatory infiltrate, and reticular dermis and adipose tissue with presence of lymphohistiocytic infiltrate with a tendency to form nodules, without vascular involvement, and small cholesterol deposits, compatible with subcutaneous fat ne crosis (SBFN) of the newborn. The patient at three months of age had complete regression of the lesion. CONCLUSIONS: a clinically and histologically compatible case with SBFN is described, that did not present complications during observation. In general, this pathology has a good prognosis, with spontaneous resolution as in our case.

Haematoma complicating subcutaneous fat necrosis of the newborn: a rare complication following therapeutic hypothermia.

A term, large for gestational age male newborn, was admitted to the neonatal intensive care unit with meconium aspiration syndrome and severe hypoxic-ischaemic encephalopathy. The baby was treated with therapeutic hypothermia using a total body cooling blanket. After 48 hours, the baby developed tender, indurated subcutaneous nodules consistent with subcutaneous fat necrosis (SCFN). The lesions started initially over the back but gradually spread to cover both shoulders, upper arms, chest area and both thighs. On day 19 of life, multiple small nodules on the back softened and coalesced to form one sizeable fluctuant swelling over the thoracolumbar area. Over a few hours, the swelling rapidly progressed to a large, tense mass with sloughing of the gangrenous overlying skin. This unusual complication of SCFN required surgical intervention for evacuation and debridement of the haematoma followed by graft repair of the skin defect.

Fat necrosis with an associated lymphocytic infiltrate represents a histopathologic clue that distinguishes cellular dermatofibroma from dermatofibrosarcoma protuberans.

BACKGROUND: Cellular dermatofibromas (CDFs) and dermatofibrosarcoma protuberans (DFSP) can be challenging to differentiate from one another. Morphologically, both entities commonly extend into the subcutis, exhibit high cellularity with limited cytologic atypia and have a mixed fascicular-to-storiform growth pattern. We sought to evaluate the significance of fat necrosis with an associated lymphocytic infiltrate as a histopathologic clue for distinguishing CDFs from DFSP. METHODS: We identified cases in our pathology database with a primary diagnosis of CDF or DFSP. Punch or excisional biopsy specimens with extension into the subcutis were selected. Previously biopsied lesions and specimens that did not interact with the subcutis were excluded. Histopathologic features were evaluated in hematoxylin and eosin stained sections. RESULTS: Fat necrosis with lymphocytic infiltrate was present in 20/20 cases of CDF. None of the 20 DFSP cases had fat necrosis with lymphocytic infiltrate although 4/20 had fat necrosis alone. CONCLUSIONS: Fat necrosis with associated lymphocytic response can aid in the distinction between CDF and DFSP.

Risk Factors for Fat Necrosis After Stereotactic Partial Breast Irradiation for Early-Stage Breast Cancer in a Phase 1 Clinical Trial.

PURPOSE: This study reports predictive dosimetric and physiologic factors for fat necrosis after stereotactic-partial breast irradiation (S-PBI). METHODS AND MATERIALS: Seventy-five patients with ductal carcinoma-in situ or invasive nonlobular epithelial histologies stage 0, I, or II, with tumor size <3 cm were enrolled in a dose-escalation, phase I S-PBI trial between January 2011 and July 2015. Fat necrosis was evaluated clinically at each follow-up. Treatment data were extracted from the Multiplan Treatment Planning System (Cyberknife, Accuray). Univariate and stepwise logistic regression analyses were conducted to identify factors associated with palpable fat necrosis. RESULTS: With a median follow-up of 61 months (range: 4.3-99.5 months), 11 patients experienced palpable fat necrosis, 5 cases of which were painful. The median time to development of fat necrosis was 12.7 months (range, 3-42 months). On univariate analyses, higher V32.5-47.5 Gy (P < .05) and larger breast volume (P < .01) were predictive of any fat necrosis; higher V35-50 Gy (P < .05), receiving 2 treatments on consecutive days (P = .02), and higher Dmax (P = .01) were predictive of painful fat necrosis. On multivariate analyses, breast volume larger than 1063 cm3 remained a predictive factor for any fat necrosis; receiving 2 treatments on consecutive days and higher V45 Gy were predictive of painful fat necrosis. Breast laterality, planning target volume (PTV), race, body mass index, diabetic status, and tobacco or drug use were not significantly associated with fat necrosis on univariate analysis. CONCLUSIONS: Early-stage breast cancer patients treated with breast conserving surgery and S-PBI in our study had a fat necrosis rate comparable to other accelerated partial breast irradiation modalities, but S-PBI is less invasive. To reduce risk of painful fat necrosis, we recommend not delivering fractions on consecutive days; limiting V42.5 < 50 cm3, V45 < 20 cm3, V47.5 < 1 cm3, Dmax ≤ 48 Gy and PTV < 100 cm3 when feasible; and counseling patients about the increased risk for fat necrosis when constraints are not met and for those with breast volume >1000 cm3.

Necrosis grasa subcutánea múltiple: correlación ecográficohistopatológica. Multiple encapsulated fat necrosis: histopathological relation to ultrasound findings.

Encapsulated fat necrosis is a benign entity that has multiple possible conditions in the differential diagnosis. Because of this, the ultrasound and histological studies become highly relevant. We present a 14-year-old boy with this condition who exhibited numerous nodules that were detected after an intentional weight loss of 20kg. The ultrasound and histopathological examinations were necessary to confirm the diagnosis. Even though there is not a clear traumatic record in all cases, trauma constitutes the main hypothesis for its development, by decreasing the blood supply to the adipose tissue lobules and causing subsequent ischemic necrosis. Similar lesions have been described in the omentum and in the breast after surgical procedures or invasive diagnostic tests. In the ultrasound study, at least three presentation patterns have been described, which might match the three histological states, from early fat tissue degeneration to ultimate necrosis and even calcification. It is important to know the clinical characteristics, the ultrasound patterns, and the histological findings of this condition for an accurate diagnosis.

Necrosis grasa del recién nacido / Fat necrosis of the newborn

Resumen: Introducción: Las paniculitis constituyen un grupo de enfermedades que afectan al tejido graso subcutáneo y se manifiestan clínicamente como nódulos. Su patogenia no es del todo clara, por lo general es asintomático. El diagnóstico confirmatorio es histológico. Objetivo: describir las características clínicas e histopatológicas de un caso de necrosis grasa, una forma especifica de paniculitis en el recién nacido (RN). Caso Clínico: RN femenino de 40 semanas, parto cesárea de urgencia por taqui cardia fetal más meconio, APGAR 7-8-9. Requirió oxigeno y presión positiva por 5 min. Al quinto día de vida presentó aumento de volumen en tronco posterior, de coloración eritematosa - violácea, remitente a la palpación, no doloroso. Ecotomografría de piel y partes blandas informó aumento de la ecogenecidad del tejido celular subcutáneo y pérdida de definición de las celdillas adiposas de aproximadamente 42.3 x 9.7 x 20.1 mm, sin presencia de vascularización. Biopsia de piel: epidermis con acantosis irregular y ortoqueratosis en cestas; dermis papilar con infiltrado inflamatorio y dermis reticular y tejido adiposo con presencia de infiltrado linfohistocitiario con tendencia a la formación de nódulos, sin compromiso vascular, leves depósitos de colesterol; compatible con necrosis grasa del recién nacido (NGRN). Paciente tuvo regresión completa de la lesión a los tres meses de vida. Conclusiones: se describe un caso compatible clínica e histológicamente con NGRN; sin complica ciones durante su observación. Por lo general esta patología tiene buen pronóstico, con resolución espontánea, como en nuestro caso.

Abstract: Introduction: Panniculitis is a group of diseases that affect subcutaneous fat tissue and clinically manifest as nodules. Its pathogenesis is not entirely clear, and it is usually asymptomatic. The confirma tory diagnosis is histological. Objective: To describe the clinical and histopathological characteristics of a case of fat necrosis, a specific form of panniculitis in the newborn (NB). Clinical Case: 40-week female NB, born by emergency cesarean section due to fetal tachycardia with meconium, Apgar score 7-8-9. She required oxygen and positive pressure for five minutes. On the fifth day of life, she presen ted an increased volume in the posterior trunk region, with an erythematous - purplish discoloration, which is soft and non-tender to palpation. Skin and soft tissues ultrasound showed increased echo genicity of the subcutaneous cellular tissue and loss of definition of the adipocytes of 42.3 x 9.7 x 20.1 mm approximately, without vascularization. Skin biopsy showed epidermis with irregular acanthosis and basket-weave orthokeratosis; papillary dermis with inflammatory infiltrate, and reticular dermis and adipose tissue with presence of lymphohistiocytic infiltrate with a tendency to form nodules, without vascular involvement, and small cholesterol deposits, compatible with subcutaneous fat ne crosis (SBFN) of the newborn. The patient at three months of age had complete regression of the lesion. Conclusions: a clinically and histologically compatible case with SBFN is described, that did not present complications during observation. In general, this pathology has a good prognosis, with spontaneous resolution as in our case.